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 | |  | March 11, 2007 - Driver development time!
Most of my track time is spent in the Seven, but it's time to start paying more attention to Miatas. So this weekend I was at the track with a big blue car instead of the usual little orange one. The Miata is supercharged (about 155 hp at the wheels, I'd estimate) and has an off-the-shelf suspension from Flyin' Miata that works very well - FM springs, Tokico Illumina shocks, FM rear shock mounts and FM sway bars. There's one of Flyin' Miata's "butterfly braces" underneath so it's a good solid chassis. I was also running a set of Toyo RA-1s that were nicely broken in and some autocross brakes. Overall, it's a pretty good test bed for the rally car as it's running the same ride height and spring rates we expect to use.
After all the time spent in the lightweight car, it's good to see how well a sorted Miata works. It's forgiving, it's controllable and it sticks like crazy. There's obviously more weight transfer going on (and this car is heavier than the Targa car will be) but it's easy to use this as part of your driving technique. The autocross brake pads weren't up to sustained hard braking, so this meant I had to carry in higher entry speeds and worked as an excellent training tool. We'll be running better brakes in the Targa.
I spent some time driving "off line" at the track, pretending I didn't know where I was going and trying to deal with very different situations than the usual ideal line. I also tried to avoid using all of the track to give myself some extra room like we'll have to do in Newfoundland. It's tricky to pretend you don't know a track that's quite familiar to you, but it's also quite eye-opening how a well-known corner changes when you enter it from a different angle! Not only did this help me improve my skills, it also illustrated quite dramatically how much of a difference it makes in speed around the track.
Luckily, there were very few cars on the track so nobody thought I was crazy.
A good day overall. Time to get back to work though!
entry 90 - tags: testing, other cars, skills | | |  | March 27, 2007 - More driver development.
I've been autocrossing my little Seven for the past few years. But it's time to start concentrating on Miatas again for a while, so I bolted some race tires and a race seat into my girlfriend's supercharged Miata and went hunting.
The event was a Corvette autocross, always a fun group to run with. My coworker Brandon - driving a turbocharged Miata with another 60-80 hp over mine - and I were the only two non-Corvettes at the race.
It took me a few runs to get used to the slower reflexes and lower grip levels of the Miata instead of the Seven, but it started to come back. Lower grip levels not just because of the different car, but also due to cold weather and a dusty parking lot - a good indication of what we can expect in Newfoundland.
It was a good battle between Brandon, myself and a supercharged 2006 Z-06 running on massive V710s. On my last run, I left the braking a millisecond too late on the last corner and understeered badly to the finish line. Brandon didn't make any mistakes and took the fastest time of the day, while the Z-06 ended up just ahead of me.
Lessons for the Targa? The adjustable brake proportioning will be quite useful and of course I'll have to leave some extra room to stop in adverse conditions. I don't have any trouble controlling the car in big slides (after the first run, I did most of my steering with the rear wheels) but sliding off the outside of a corner in the Targa with locked-up brakes is something to avoid.
entry 103 - tags: testing, other cars | | |  | June 16, 2007 - The first drive!
It wasn't much. I drove the car out of the garage and did a short run up and down the street. I probably spent more time doing three-point turns than driving. But it moves! A longer test drive will have to wait until I fix a bad exhaust leak (left a clamp off) and get a little more comfortable with the ECU so I know the engine is getting the fuel it needs. I do have the car registered.
However, I can report on initial impressions. It feels very, very eager. The engine has that sharp, low-inertia feel I'd been hoping. It's going to be a great engine once it's tuned and I can explore full throttle, just blipping it reminds me why I like high compression so much. The clutch is nicely weighted and even without a power steering belt the steering isn't excessive.
I can't wait to get this up and running completely.
entry 214 - tags: testing | | |  | June 16, 2007 - It wasn't a perfect test drive.
The car was idling high, indicating a vacuum leak. Popping the hood showed that it wasn't just one vacuum leak - I hadn't bothered to do anything about a bunch of vacuum ports on the intake manifold, two or three of which are in this picture! Whoops. Well, at least it's not a complicated fix.
entry 215 - tags: testing | | | June 17, 2007 - The car also had an exhaust leak on the short test drive.
The two-piece midpipe didn't have a clamp on the slip joint, so I figured I'd put that on. And I discovered that I'd left the entire exhaust system put together with bolts that were just finger tight. Well, it's not difficult to solve that particular problem. It should be nice and quiet now.
I've also fixed the vacuum leaks and painted the headlight covers and fuel door. Now I have a complete white body. All I need to do is read the manual for the ECU cover to cover a couple of times so I can break everything in properly...
entry 216 - tags: exhaust, testing | | |  | July 5, 2007 - Bill Cardell stopped by on the July 4th holiday to help me take the car for its first significant run.
We bolted on the hardtop, fixed a small brake leak at one wheel, set the timing and then headed out for a spin. The car did very well overall. The fuel and timing maps, based on a "best guess" by Jeremy at Flyin' Miata, are pretty close and the autotuning abilities of the Hydra Nemesis will take care of the former quite easily.
The car feels good. The engine comes on cam at about 4000 rpm and pulls strongly up to my self-imposed redline of 5500. I'll stretch the engine past that next time I go for a drive. The steering was surprisingly light even without the power steering belt installed, but I'll have that fixed soon. It's too early to say anything about the suspension as it's currently on junkyard parts. Brakes feel strong though. Overall, it's giving the impression of being a very promising, entertaining car.
It wasn't completely free of problems, of course. The temperature gauge on the dash isn't working, but that's an easy fix because it's a very simple system. I wired the fans off the same switch which seemed easier at the time, but having them staged makes more sense and takes a load off the wiring. The front tires rubbed on light corners but I think I have that sorted now by bending some mounting tabs for the inner fender liners. The lack of a windshield made the car fairly drafty as well.
Time for more driving! And then the masking for the new paint job.
entry 237 - tags: testing, tuning | | |  | July 15, 2007 - The Targa Miata visits the track for the first time.
I didn't take it out at all, it's not ready for that sort of use. I was the support vehicle for the FM Westfield. But I did put about 50 miles on the car today. There's a lot of tuning left to be done on the engine management and I did a bit of that today. It certainly has that very eager lightweight feel that I enjoy so much. The lack of a windshield or rear window helps exaggerate that of course! The car had very few problems and although the suspension leaves a lot to be desired, it will grip quite well already.
Getting the car out of the garage also let me walk around and look at the stripes from a few angles. The rear is great, I love it. It does the job of highlighting the rear arches. The way the front loops around is less successful, but I'm getting close. The recent change to the straighter, lower stripe was a good one. The car looks longer because of it.
A good day, but I'm a little windburned.
entry 244 - tags: testing, Martini | | |  | August 9, 2007 - Out of the garage!
The Targa Miata visited Flyin' Miata today for the first time. Well, it's been there before, one piece at a time. But this is the first self-propelled visit. The car behaved itself and all of my coworkers were suitably impressed with the paint job.
I spent enough time looking at the car from a distance to start spotting sections of the stripes that I could have done better. It's time to get the decals on the car and distract myself from all that, I think.
One good note - the silicone on the rear window is slowly drying and going clear. In another couple of days, it should be all done.
entry 280 - tags: testing, Martini, lexan window | | | August 14, 2007 - So, how does it drive?
The engine isn't fully tuned yet so the car doesn't have full power, nor does it like to idle much. But ignoring those little foibles, it's a blast. The car is conspicuously light. It's surprising just how much difference an extra 300 lbs can make to a car, but it will happily surge forward on even just a tickle of the throttle. Even in the semi-tuned state there's a real snap to the throttle response. The car wants to run, and the short gearing exaggerates this.
The power steering is very light. A bit too light, perhaps. I'll try disabling it to see how that feels and if I'd want to deal with hundreds of kilometers of shattered roads without it.
The car is very rigid, with absolutely no flex - even compared to a modified Miata with a butterfly brace, structural foam in the frame rails and a rollbar. Amazingly, there are no rattles although there's a fair bit of noise and vibration through the uninsulated chassis and competition motor mounts. It's also rather warm inside as the engine and exhaust heat gets nicely transmitted. I'll have to do something about that.
The springs are stiff, but the Öhlins shocks control them very well. It'll be interesting to see how well that works on the track even without sway bars.
In short, the car is a ball to drive. It's a reminder that it's not just a Miata with a cool paint job.
entry 291 - tags: testing, stiffness, suspension | | | August 14, 2007 - Ready for the track day.
Three years ago, my Seven made its public debut at the Flyin' Miata Open House as well as its first serious track testing. This year, it's the Targa Miata's turn. There's a lot of interest in the car so it's going to be fun.
For final preparation, Brandon and I bolted on a new right rear caliper to solve a problem with the handbrake sticking on. Hopefully the rotor will be okay, a coworker drove the car about 1/2 a mile today with the old caliper siezed tight in place. Stinky!
The engine tuning was given a bit of a tweak today as well. The engine isn't putting out full power, that's fairly obvious even if we didn't put the car on the dyno. Still, it should be safe to run on track and the engine is very eager and flexible. At least it will idle happily now!
And voila. A bit of cleanup for the interior and I'm ready. Just in time, too!
entry 292 - tags: testing, brakes, tuning | | |  | August 19, 2007 - Time for the kids to come out to play.
I managed to get both the Targa Miata and my Seven out to the track together - and since I was running the day, I got to schedule myself into two run groups so I could run both cars. Ah, it's a tough life.
The event was the Flyin' Miata Open House, and the track is actually a large kart track. We've found that if you run it backwards it is a more challenging track, with a larger variety of corners including one downhill sweeper into a tight braking zone that is pretty tough. In a fast car, you have to make the choice between braking before a little kink or waiting until afterwards, in which case you don't have a lot of room for error. A number of other corners conspire to catch you up and it's a very fun challenge.
entry 293 - tags: testing | | |  | August 19, 2007 - The first session took place in a light rain.
Great, just the way I like to test out a car for the first time. Other than about 200 road miles, the car was completely fresh.
On this first session, the car was a handful. It would understeer on corner entry then light up the rear wheels and oversteer on the exit. It didn't help that I had brand new RA-1s on the car that hadn't been heat-cycled yet and I never got around to installing sway bars! It was a bit of a challenge.
The one thing that did stand out, however, was the engine. It's a hero. Sharp throttle response, lots of torque from deep down and a killer top end. I thought there was something wrong with the tach - I use that to judge my speeds on this track because I know it so well. And in a couple of places, I was pulling almost as many rpm as I do in the Seven - a car that weighs 1300 lbs!
It's cool seeing the action shots of the car, partly to see how the stripes work. This picture was taken in light rain, but the blinding white and the orange-red colors jump out just the way they're supposed to. Excellent. The headlights are up because I forgot to put them down, no other reason.
entry 294 - tags: testing, Martini | | |  | August 19, 2007 - After that first session, everything dried up and I got faster.
My best lap on the first session had been a 1:12.049. I was concerned that the wheelspin on exiting hard right corners and a banging noise was due to a possibly bad shock, so I bumped up the damping a little to see what would happen.
The results? No real change in the behavior of the car, but then again the track conditions were quite a bit different. The tires were biting now on turn-in, and the combination of excellent initial grip and no sway bars made for a car that required a fairly light touch. I let Bill Cardell from Flyin' Miata take the car out as well and we agreed that the lack of traction on corner exit was probably a wheel lifting. The Torsen differential used in the car is nice when both wheels are on the ground, but once one lifts it acts like an open diff. The lack of sway bars and resulting body roll meant I was getting a lot of droop on the inside rear wheel, and the short Ohlins shocks didn't have a lot of droop to provide. This is something that could be solved by lowering the car - not good for the Targa - or by limiting the roll a bit more. I did test, and the car dealt very well with big bumps such as driving over the kerbs in the chicane.
My time dropped to 1:08.527, mostly due to the dry pavement. This picture was taken on the most difficult part of the track, as I'm accelerating hard downhill towards a braking zone that has the car up on its toes. On my first hard lap, I didn't have the car properly settled before nailing the brakes, and I was rewarded with a spin. Right, no sways and 2050 lbs instead of 1300. After reminding myself of that, I was able to take the late, gutsy option without drama. This corner is an excellent one for dialing in brake balance.
entry 295 - tags: testing, brakes, suspension | | |  | August 19, 2007 - Turn one was a bit of a fast one.
As the day went on, I was starting to figure out how to drive the car better. The biggest trick was getting a good drive out of corners, and it led to me taking some different lines than I usually do in the little lightweight weapon. The Seven has a huge amount of traction, but in the Targa car I was taking wider lines to settle the rear down first. It was paying off, my fastest lap dropped to 1:07.977.
I've found a satellite picture of the track here . We were running counter-clockwise, and the big sweeper is the fun part. My goal is to start braking when my left front wheel hits the kerbing before the hairpin.
entry 296 - tags: testing | | |  | August 19, 2007 - It wouldn't be a track day for me without an oversteer shot!
I was able to throw the car around a bit. By this point, I'd figured out that my banging noise was probably the exhaust hitting the differential. I knew that clearance was tight there, I'll have to get back underneath and take a peek.
The 1:07.977 was my fastest time of the day, and it was a pretty good one. By comparison, a turbo Miata with 225/45-15 Toyos (well scrubbed in) and the JIC shocks turned a 1:07.119. Another turbo Miata was close behind with a 1:07.337, both driven by coworkers of mine. And the Targa Miata was third, ahead of another 45or so Miatas. It was an excellent first day out. The fastest car on the track (1:03.733) was my little Seven, to my satisfaction.
So, what did I learn about the car? I'd like to try a nicely sized front sway bar to cut down the roll, and maybe a bit more front camber. That will make the car easier to throw around, something I'll need to be able to do on the Targa surfaces. Unlike the track, I'll be reacting a bit more instead of anticipating.
The braking is very light, almost to the point of being overassisted. It's the first time I've tried these brakes with the larger booster and master from the late Miatas, and that could be the reason. It could also be the street-only pads I was running (you could smell them at the end of the day) and the fact that I was jumping out of the Seven which has a very firm unassisted pedal. After the first lap, it wasn't really a problem so it may have been acclimatisation. Still, I'll get some proper pads in there and see.
The shocks are the big question. They do an excellent job of damping surface imperfections. But can I run the car high enough to get the ground clearance I need for the Targa? I'll have to drop the rear down a bit and see how it works. There's another set of shocks sitting at work that have 5" of travel and I want to try them next.
entry 297 - tags: testing, other cars, brakes, suspension | | | September 7, 2007 - Track test for the new suspension.
This was an informal and short window of opportunity, but it was enough to take the car out with the new setup. I spent some time on the phone with the suspension engineers and learned about bit more about how my valving worked.
On the track, the car felt pretty good. It took a few laps to discover where the difference lay. The first hint was the chicane area. There are some big berms here and the car is usually dancing around due to the kerbs throwing the car around and the nature of the entrance to the turn. Not today. The car was just swallowing any bumps, including ones where it was off balance before hitting the kerb. Coming down the hill into the tough braking zone, I discovered that it was impossible to upset the car. I started provoking it, coming in off-line and hitting berms when the car should have been vulnerable. Nothing. It just stopped. I think the endless rear travel kept the rear wheels on the ground no matter what, adding greatly to the car's stability.
A bit of experimentation with compression damping helped balance the car a bit better and gave it more composure in the corners. At the end of the day, the car was forgiving and able to deal with just about any imperfections I could find on the track. Imperfections like dropping off the outside of kerbs on corner exits, or cutting corners so that I'd drop inside the kerbs, or hitting kerbs under hard braking. It isn't quite the super-playful Miata yet but I have some ideas for extracting the last bit of fun.Maybe a little more front camber and a front bar to encourage faster turn-in and a slightly flatter stance. I don't want too much of a wayward tail for the Targa, though. On the street, the car feels good.
There's a set of 8" 350/275 lb springs on the way along with some rubber snubs to limit the travel a bit better than my rough-and-ready bumpstop arrangements. The spring rates are closer to what I'd like to run on the Targa, although the way things are working right now I'm not sure how critical that will be! They're also an inch longer than my current setup so I can get a little more ride height, and throw some relatively soft sways in there as well.
Tomorrow, Targa 2007 starts. Good luck to everyone!
entry 309 - tags: testing, suspension | | | September 29, 2007 - The sways are installed.
There's a 7/8" bar on the softest setting up front and a 5/8" bar on the softest setting in the rear. I considered using the 14mm Mazdaspeed bar in the rear, but the aftermarket version has longer arms so I suspect they're about the same in the current setting - and this gives me more options. This current setup is slightly more biased towards front stiffness than I usually run. Typically I'd have that rear bar on the middle setting. I also have a factory 12mm rear that I can throw on if required. One nice thing about the Targa Miata is that I can install the rear sway bar without even jacking up the car, thanks to the cutaway rear bumper!
I headed out for a run to test the bars. To make things more exciting, the wind was howling and rain was splattering down. It's the best imitation I've seen of Newfoundland weather here in the Colorado desert. I'm assuming I won't have to dodge tumbleweeds in the rain in Newfoundland, though.
The car feels great. It's got a very nimble feel and it just glides over imperfections in the road over 20 mph. Below that speed there's more impact felt through the body but the car just deals with it. One 2nd gear corner with a very corrugated exit caused the rear end to lose traction, but it had more to do with the cool tires, wet road and too much power than with the damaged pavement. The Torsen diff let the loose wheel just spin up, an indication of how little traction there was. It was a smooth breakaway and I just rode it out. The car is very eager to turn in and feels a bit darty, but that could also be the strong cross winds. I'll see how it feels over the next few days. The next track session is scheduled for November 3rd, but I might be autocrossing the car next week. We'll see.
entry 320 - tags: suspension, drivetrain, testing | | |  | October 14, 2007 - Autocross baptism.
I've heard the Targa described as a combination of an autocross and Solo I racing. So I'm using both types of venue to test. This autocross was put on by the local Corvette club. They allow a small number of "metal" cars to participate by invitation, and I'm usually welcome. So I brought out both the Miata and the Seven.
So how did the car do? Quite well, really. I learned that it's quite easy to drive on the autocross course, with great braking ability and a nimble feel - just what you'd hope for out of a light Miata. The car's easy to drive although I'd like a little more feedback on a locked wheel.
What I didn't expect was the inability to put down any power. Again. It's not a wheel lifting this time, but it sure does act like it. I'm wondering if the Torsen LSD is actually a Torsen. Maybe I got my hands on an open diff instead. I never actually checked inside the casing. I have a good differential in the Seven that would work well in this application, but I hate to take it out.
On my third run, I almost entered a trance and just drove around the course. No real effort was involved, the car just did what it was supposed to. The end result? A time that was 0.3 seconds slower than a rotary-powered Fiat X1-9 autocross special and a C5 Z06 Corvette - good enough for fourth fastest of the day out of a field of about 24 cars. First place was, of course, the Seven.
So, in all a very good day. The car performed well despite a real weak point and showed no evil handling characteristics. That's about all I could ask at this point!
Video now available!
entry 324 - tags: testing, other cars, drivetrain | | |  | November 4, 2007 - Off to the track.
It's a five-hour drive over multiple high passes, and we're leaving at about 6 pm. Makes for a long day. I've decided to tow the car for two reasons - one, we're expecting temperatures well below freezing and the car has no heater, and two, it means that my wife Janel will travel with me. It's much more pleasant.
The trailer may not look like much, but it's easy to load and tows very nicely. As it turns out, it was really good I had it.
entry 334 - tags: testing | | |  | November 4, 2007 - The track day was with the Peak-to-Peak Miata club and took place at Pueblo Motorsports Park.
I was last there in March and it's a track that's fairly familiar to me. Not the greatest track in the world, but it does have a couple of interesting corners. More importantly, the club runs the track day as an open format. There are no run groups, so you can enter and exit the track whenever you want. This makes it excellent for both driver and car development and takes a lot of the tension out of a day. It wouldn't work with a group of unknown drivers, but these days tend to be invitation-only and everyone uses their heads.
For me, the goal was to sort the handling out and see how my new alignment worked as well as test the suspension at high speed. The first few laps felt good - the car was composed, but it was uninspired. There was a little bit of understeer. Very stable, but I didn't have the adjustability I wanted. So I installed a stock 11mm rear sway bar, as the car had been running without one. As you can see, the trailer makes an excellent sway bar adjustment rack.
That was better. The car was a bit more adjustable and turned in better, but it still wasn't quite there. I popped on a 14mm rear bar from a Mazdaspeed MX-5 and voila, we have a Miata. The car came alive with a great handling balance and excellent adjustability. It could dance.
Meanwhile, I also took a few sorties to work on the suspension tuning. A bit more rear compression damping, a touch more rebound and the car was able to handle just about anything on the track. I was driving over berms and trying to upset the car, but to no avail. One corner did give me the ability to bottom out the suspension, but I had to hit a berm at full cornering force to do it and it didn't upset the car at all. Once again, I found that I could move the rear end around if I wanted but it was still very easy to control. I believe this is due to the long travel available, keeping the wheels well planted on the ground. There are other suspensions out there with decent travel, but most will unweight the spring before reaching full extension. Not in this case!
There's one spot on the track where the exit berm on a corner has big bumps or teeth in it. On one lap, I brought the tail out on this one and went around with the rear wheels going over the teeth at full throttle. It was bumpy, but it didn't upset the car. That's the sort of composure I need.
The last turn on the track is a fast one that has widely varying surfaces as it travels across a drag strip. This means you go from patched asphalt to VHT-soaked asphalt to coarse concrete to VHT to asphalt again, with a couple of metal plates thrown in for good measure. Oh, and it's bumpy and you take it at wide open throttle in 4th gear. In a stiff car, it's painful and the car keeps skipping around. In the Targa car, I could feel the changes in lateral grip but the car didn't get upset at all. Very nice - I think we have a winner with this suspension setup. The Torsen differential was working as intended as well, putting down the power smoothly and cleanly.
So, all very promising then. I was able to run down and pass a Spec Miata which was gratifying, as he was running a much more track-biased suspension than I was. His front spring rates are more than double mine! There was a good battle with a Subaru STi that was promising as well, my handling and grip were able to make up for a 150 hp (or so) shortcoming.
Bill Cardell of Flyin' Miata tried the car and was impressed. The suspension he considered to be "suitable for a NYC taxi" because of the way it would absord anything. The engine feels good but it really needs more top end, that's something we'll work on. His only concern was the brake bias, as I have it a little strong in the tail for maximum braking. This means that the tail feels a bit loose in some situations. Not a problem on the track where you know exactly what the next corner looks like, but he pointed out that with the unexpected nature of the Targa course this could be a liability. Luckily, that's easy to adjust, even between corners.
So that's the good news.
entry 335 - tags: testing, suspension, brakes | | |  | November 4, 2007 - An unfortunate finish to the day.
Bill took the Targa car out to see how it was working, and I borrowed his Westfield. The little car was working beautifully and I was quicker in it than I had been in the Miata. With 700 lbs less weight and only a bit less power, that's not a big surprise. Bill wasn't lagging too much, though, and some slower traffic bunched us up. Shortly after getting free, we entered turn 5, the best turn on the track. It's like a baby version of Eau Rouge, as one driver pointed out - an uphill corner with a nice compression at the bottom and a blind exit. Very entertaining and nicely quick. I came out of the series of bends and noticed Bill was gone from my mirrors - and there was a big cloud of dust on the inside of 5 with a Miata shape inside. The car had stopped just short of a flag station and tire wall.
Back in the pits, we saw the typical damage for an off-track excursion around here - one tire pulled off the wheel and another with grass jammed in the bead. There were some scuff marks and scratches on the nose as well.
We pulled the wheels off and headed for the local Discount Tire. I was still wearing my driving suit, and when I got out of the truck a little kid asked "are you a racing car driver?". Not really, but I'm trying!
The staff at Discount were really helpful, getting right to work despite the fact that it was the middle of a busy Saturday. They pulled off the tires, vacuumed them out (to our great amusement) and reseated them in about 4 minutes. Then we were called in to have a look at the balancing machine. One wheel was wobbling badly. There are custom-made SSRs and can't be replaced, nuts. It's a good thing that I have access to a total of 8-12 of them.
Oh well, we figured we'd see how it felt. After all this, the tire shop didn't even charge us! Note to self, always wear Nomex to a tire store. Thank you Discount.
Back at the track, the tires went on and I headed to the track for some gentle exploratory laps. Heading down pit lane, I noticed that my steering wheel was off center. That was it, I headed for the trailer. Between a potentially shaky wheel with some damage and unknown suspension problems, it was not time to go push hard.
Nothing was obviously bent under the car although it appears one of the caster adjustment cams might have slipped. I didn't get the chance to mark the suspension settings before loading on to the trailer, unfortunately, and this simple change may account for the steering wheel offset. I'll check that out shortly. The paint damage is all on the lower half of the front bumper and should be easy to fix.
A sad finish to the day, but nothing that can't be repaired fairly easily and nobody was hurt. We never did figure out exactly what happened to cause the off, from looking at tire marks I think the car simply ran out of grip, possibly brought on by a slight crest in the track there. This is why we test on the track instead of the road, though!
entry 336 - tags: testing, other cars, tires, crash | | |  | December 7, 2007 - Video time!
A friend of mine gave me a DVD of the car at the autocross back in October. Of the six runs I took, only a couple have any decent video. Still, quite instructive. Naturally, the car's development has progressed since that point but there is some behavior visible from outside that I'll take into consideration.
I've tried a different video setup than I've used on previous websites, using the DivX web player. I like the video quality and the ease in which you can pop it out to full screen. Comments are welcome.
Besides, if you've been watching the WRC footage as I have, you already have DivX on your system. Congratulations to Loeb for the world championship!
See the videos here.
entry 346 - tags: testing | | |  | March 10, 2008 - Time for another test.
After a long tow through some nasty weather (check out that filthy hood!), we made it to Pueblo for the most recent testing session. The goals for this one were primarily to work on the driver/navigator team, although as always suspension tuning was involved.
After a late start due to a car that was stuck on the track with the doors locked and the engine running (!), I took the car out solo in wet (and rapidly drying) conditions. The brakes didn't feel good. A nice solid pedal, yes. But I wasn't getting much feedback. This kept up over the whole day so I'm not sure what's going on or if it was just a matter of a lack of faith on my part. Since I was planning on making some big changes to the pads shortly, I'll look at them more closely later.
The car felt pretty good. The handling balance with the new alignment wasn't right on the first session, it was a bit too biased towards understeer as I'd expected. Not terrible and certainly stable, but I do generally prefer a car that's set up to be a bit on the loose side. The suspension was swallowing up just about everything. Just about?
The final turn has been reconfigured to make it much tighter than before. It will be repaved this summer, but for the time being it's rough. Really rough. There was a deep dip in the pavement right past the apex that was bottoming out the suspension hard. When I crawled under the car to do some sway bar adjustments, I noticed that the left rear spring had marks indicating it had hit coil bind. Ahh, that's not good. The fairly high ride height and the 8" springs were a bad combination. Since I didn't have any way to deal with it, I played with the corner to avoid that hole for the rest of the day. Elsewhere on the track, I was able to drive over berms - even the rough "dragon's teeth" ones - with impunity. So that was working well. Despite a slight understeer in fast sweepers, the car was both faithful and mobile when I was setting up for corners so it's probably a pretty safe setup for the Targa now. It was quick enough to let me pass a Lotus Elise without any difficulty, that's a good sign.
I'm going to try a couple of things to sort out that coil bind. There are a set of 10" springs on the way to replace my 8" ones, as they'll give an extra 1.25" of spring travel and that will avoid the binding. They're a 250 instead of my current 225 so I can make the rear slightly more mobile. I also ordered some 375 lb springs, thinking I could try a 375/300 combination instead of my current 300/225. The stiffer springs not only give an extra 0.5" of spring travel, they'll use a lower perch height for the same ride height so binding should not be a problem. Now, do I want the extra stiffness or do I keep the car fairly soft? I'll have both options available to me.
The header worked perfectly all day, not showing any signs of weakness or cracking. That's good.
entry 431 - tags: testing, suspension, header | | |  | March 10, 2008 - What about in the car?
Once I'd roused Janel from the comfort of a warm tow vehicle, we discovered that our concerns about nausea were unfounded. With the rally computer to play with, she was distracted and forgot to get sick. Excellent!
The intercom worked well, allowing me to hear her clearly. She couldn't hear me quite as well - probably because the speakers were further from her ears - but that's a good setup. I did discover how hard it is to concentrate on driving quickly while also carrying on a conversation about how the trip computer works. Once the communication became more one-way, I was able to work better on dealing with the inputs.
For one session, she brought along a book and read it to me. Seems like an odd test, but we didn't have pace notes for the track, you see. Again, no problems with nausea as long as she kept her legs braced and didn't let them flop around. So the track day was a good test then. We learned a few things, that was the goal.
Eric asked for a picture of the whole interior in the mostly-final configuration. Here you go!
entry 432 - tags: testing, skills, computer, intercom | | |  | March 30, 2008 - Autocross time!
The Corvette club was holding another autox, so I brought out the race car to see how the new suspension would sort out. Last time, I was hampered by the open differential but still posted a good time. Let's see how it works this time.
The lot was dusty and it was relatively cool, so it was a good test of the ability to put power down. Which turned out to be a challenge. Despite the Torsen diff, I was still getting wheelspin on the inside rear wheel exiting right turns. This is frustrating. It wasn't a problem on the track a few weeks back and it was only apparent on the tight confines of an autocross course, but still - I thought I had this licked. I'm going to do a little more poking around. Course workers confirm that the inside rear was simply unloaded and just spun up. A Torsen will go fully open when there's just no traction on one corner. I could throw in a preloaded Guru differential for the track day next weekend, or maybe I'll just let it stay as is so I can do a direct before/after comparison.
The first few runs showed that I had the ability to light up the rear tire(s) and slide the rear end around, but also that the car seemed to have some understeer in the few steady-state corners on the course. So I softened the front sway bar slightly to see if that sorted the problem. Yup, the car was much happier. It may be a little too biased towards oversteer now, but we'll find out next weekend on the kart track. Right now, it'll do exactly what I ask it to and can really be moved around on demand. Of course, that's with a maximum speed of 57 mph according to the rally computer. How will it do at 120?
I was also playing with the brake bias, thanks to the new pads. For a couple of runs, I had too much in the rear. The final braking zone took place in the middle of a big sweeper, so the car was unbalanced to begin with. On one run, I was countersteering fairly enthusiastically to keep the rear wheels behind me as the car wagged its tail into the corner. It worked, though, and a quick twist of the proportioning valve sorted that out. By the end of the day, I had the brakes dialed in pretty nicely and the car was mobile yet controllable under braking. Of course, I'll have to do it all over again once the new pads are installed.
So, how did it do? Well, there was an STi on sticky tires in attendance. Try as I might, I couldn't get within a half second of him. But Brandon and I were locked in a great battle. He has an extra 110 hp and Azenis tires, while I have the Toyo RA1s. It turned out to be an excellent match, going right down to the wire. The final margin was 0.079 seconds, with me being slightly faster. What a great race. I managed to come in second overall, which is not shabby at all. None of the Corvettes able to keep up with the three fiercely battling "metal cars". The fastest 'Vette was 1.8 seconds behind us.
Brandon, if you're going to strike a goofy pose for the picture, I'm going to take the picture!
entry 444 - tags: testing | | |  | April 5, 2008 - Another trackday test.
This was on our local kart track, the same track used for the car's first track day. I wanted to see how the suspension was doing, and see if the car could put power down.
Immediately it became apparent that the track was fast today. My existing lap record fell almost immediately to a turbo Westfield. That was set in the Seven, so I didn't have a chance to fight to get it back. My own times were quick as well though, as I ran times that were quicker than we've seen from Miatas here before. Recent rain has left the track much cleaner than usual, I suspect.
On track, the car felt great. The suspension is almost perfect, allowing me to take completely ridiculous lines through the chicane. I wasn't just putting the wheels on the berms, I was dropping off the other side and essentially straight-lining the course. I never bottomed out and the car wasn't upset at all. Only once did I scuff the bottom of the car, and to do that I had to put my outside wheels where most people ran their inside ones! We shot some video of the car from behind that shows my fairly ludicrous lines, I'll have that posted before too long. When I took my friend Mark (last seen welding the roll cage into the car a year ago) out for a ride, he was amazed. "It doesn't feel like a Miata, it feels like a rally car!". He was also impressed with the feeling of stability and adjustability in the car, as it just gripped and gripped and never seemed to get upset. The car and I are bonding, and it's become a very useful tool. Bill Cardell took a break from hammering on my lap record to take the car out for a run, and he was quite impressed with the setup as well. The new brakes with the Performance Friction front pads really worked nicely, hauling the car down remarkably fast with lots of stability. There are a couple of corners on this track that really test both braking and stability so it was a good venue.
Unfortunately, the car again showed an inability to lay down any power in a right turn. I started running with ballast (aka passengers) after the first session, and that seemed to help somewhat. But still, it's acting just as if there's an open diff back there. So either I got it wrong and installed an open (again!), there's something wrong with my Torsen (I can't think of how that would happen) or for some reason the suspension setup is unweighting that inside wheel. Given the amount of droop travel available, I doubt it's the latter. The car feels exactly like it did with the open diff back at the Open House testing, although I blamed a short-travel suspension for the behavior then. So step one is to confirm it's a Torsen for sure for sure. I'm also going to cornerweight the car and see if it's way off, but still. A turbo Miata running almost exactly the same tires (225/45-15 instead of 205/50-15) and an extra 130 hp was not having the same problem.
So how did I do? Well, I had the fastest Miata there at 1:04.989, running clockwise. That's 1.5 seconds faster than we've seen a Miata go around the track in that direction, I think. Running counterclockwise, I ran a 1:05.228. I even beat that turbo Miata on race tires. The only cars that went faster were the turbo Westfield and that STi from last weekend. No shame there! In the case of the turbo Miata, it was a matter of suspension versus horsepower again. That car's fitted with a JIC Magic suspension and is very competent on the track. It's just not quite as competent. That car was also being piloted by a very good driver who knows the track well, so it's fair to say that most of the difference was in the car.
entry 445 - tags: suspension, testing, brakes | | |  | April 9, 2008 - Video time!
I've just added three videos of the car running through the chicane at the recent track day. Honestly, the videos downplay the size of the hit the car is taking, but you can still get an idea of how well the suspension is coping. I don't know if I have an in-car shot yet or not.
For those who are wondering, the chase car is a turbo Westfield.
First pass
Second pass
Third pass - the car is completely unruffled in this one.
I forgot to mention in my last update that I set the lap record for Miatas last weekend. Not bad!
entry 446 - tags: suspension, testing | | |  | April 9, 2008 - Another video is up.
This one's a full lap of the track from behind the wheel. You can read more on the video page for this video.
Watch it!
entry 447 - tags: testing | | | April 20, 2008 - I put the car back together and took it out for a test drive this morning.
The upper rear control arm bolts are a bit looser to allow for free movement of that arm.
I used a piece of road I haven't used with this car before, but it's perfect for per-Targa testing. Incessantly twisty with a lot of blind corners, covered in gravel in inconvenient places and with completely hammered and badly patched pavement.
The car did quite well. I wasn't at full throttle very often but I never had a lack of traction. Even at inadvisable speeds through the roughest, twistiest sections the car never got upset although it did make some interesting movements. I'll have to go back through there with a more normal car to get a baseline. I'm also going to take Janel for a ride to make sure she's comfortable with it!
entry 451 - tags: testing, suspension | | |  | May 25, 2008 - I took the car out for a run on the local "Targa simulation" road.
It's rough and twisty and gets gravel on it. I wanted to play with suspension settings a bit as well as see how the car does with putting down the power out of corners.
The suspension setup worked just fine. One hammered area had the car moving around a bit much, but a slight tweak to the rebound solved that nicely. As for the inner wheel wheelspin on right hand turns - well, it doesn't seem to be a problem. I'm realizing that both the autocross course and the local gokart track are much tighter than most turns in the real world. On the "big track" at Pueblo I don't have a problem. So, I think I'll just let this slide - or just bung the Guru in for the race and avoid it completely.
I'm still driving at "fast road" speeds, though. There's an overall speed limit of 200 km/h (120 mph) during the race, and in the open sections I'm trying to imagine going 50 mph faster. And having Janel deal with me going 50 mph faster. She's been alongside me at 10/10ths on the racetrack, but I think it will be quite a different matter on real roads.
The list of things to do for the race is getting shorter, but no less critical. I still have to add a door bar (a different focus in the regulations here) , figure out how to mount my tools (and what tools to bring) and deal with a number of small things to ensure I don't have a hectic day running around St. John's to solve problems. But it's starting to look pretty good. So maybe I can start working on engine output again.
entry 460 - tags: testing, suspension | | |  | June 1, 2008 - Autocross time!
This was an event put on by the Red Rock Racers, a group I started because we didn't have any autocrosses to go to! Problem solved, now there's one a month. And on the prettiest autocross course in the world.
We had a good bunch of cars out - a couple of modified STis (including one on Toyo R888s), a rotary-powered X1/9, some quick Miatas, an Evo and even a Isuzu I-Mark "Handling By Lotus". Everyone's a lot of fun to run with. However, they did have a little trouble keeping up with the Targa Miata. I took the fastest time of the day by a 0.8 second margin.
The car felt good, moving around nicely and easy to toss into corners and transitions. I was using the brake bias to adjust the handling of the car and it worked well. I didn't adjust anything on the suspension after my recent over-the-road testing otherwise.
The picture was taken on a fast right sweeper, and you can see there's a fair bit of body roll. It didn't seem like it from inside the car and it responds to transitions pretty well. But I was still having traction problems on rights, and looking at that roll makes me wonder if it is simply a matter of unloading the inner wheel completely despite all that droop. I'm going to play with some different sway bar and alignment settings, although having Janel in the car helped and I expect a cornerweighting session would also plant that right rear a bit more.
Another thing that concerned me a bit was my consistency - or lack thereof. I'm usually pretty good for putting down similar times, but today I was all over the place on the timing board. Still at the pointy end of the pack, of course, and I posted not only the fastest time but also the second-fastest and (I think) fourth and fifth-fastest. But there was a bigger range than usual. I'm not sure exactly why. I did manage to stay clear of cones all day though.
The car was burping coolant out of the overflow tank, but not showing signs of running hot. I think I might have a bad radiator cap that's venting early. Easy enough to check. Otherwise, the car ran flawlessly.
entry 462 - tags: testing, suspension, brakes | | |  | June 7, 2008 - Of course, while they were here we had to visit the track.
And Tom jumped into the passenger's seat to take a few laps with me. He speaks German and Portuguese, I speak English and French. But a big grin comes across pretty well regardless!
So, how did the car do? Well, it handled everything with aplomb except for the track sessions. I took the car out first and soon discovered that it could not hold any coolant and overheated badly. After it cooled off, I pulled the radiator cap off and discovered that it was in terrible shape. I wonder if it was a temporary one from a junk car that I put in place while building? Anyhow, it's going to have to be replaced.
We stole the cap off Janel's car and went out again. Still a problem, possibly due to air bubbles after a big coolant blow-off with the bad cap. But the radiator did come out of an older car, so I'll pull it and clean it.
This track is excellent for testing cooling systems. It's at high altitude, has low humidity and has low average speeds - it's a worst-case scenario for cooling. The high was also getting pretty close to 90F. So if the car's ever going to have cooling problems, this is where. We were also running longer sessions than usual here. I don't anticipate cooling to be a major problem in Newfoundland, but if I can keep the car happy here after 15 miles of full throttle in second gear, I'll never have to worry about it.
Otherwise, the car did pretty well. It was at the track along with The Seven, which does have the tendency to make anything feel a little fat and slow. The Targa car has a very different handling balance because it's built for a different purpose. It's less prone to oversteer (no, really!) and more forgiving - as it has to be. But I think some of the things I learned building the Miata will get transferred to the Seven, just as the knowledge from the Seven helped me build the Miata.
entry 464 - tags: testing | | |  | June 7, 2008 - At the crack of dawn, Janel and I took off for Glenwood Springs to try our hands at a TSD (Time-Speed-Distance) rally.
There's actually a TSD aspect to the Targa in the Grand Touring class, but we're not running that. Still, we figured the experience would be a good one, allowing us to spend some time in an organized rally environment that's fairly low pressure. And with cool cars. There were at least 60, including two or three other (stock) Miatas and a newer Corvette. Pretty much everything else was a classic.
Let me tell you, rolling up into a parking lot full of vintage cars in a stickered-up and Martini-liveried car with a full rally computer, well-broken in race rubber and your names on the roof makes you feel a little conspicuous. And people certainly don't believe you're novices!
entry 466 - tags: testing, skills | | |  | June 7, 2008 - Janel, hard at work watching for instructions.
A TSD is more of a treasure hunt than the Targa is, and there wasn't as much navigation as we would have preferred. They have to be run in rural areas, though, and rural in Colorado means you don't get a lot of turn-offs because you're usually running along a valley or climbing a pass. Still, we did get much more familiar with communicating with each other, dealing with problems ("I said slow down!" "But it's sooo boring!") and Janel got to spend lots of quality time with the trip computer.
All joking aside, despite the warnings of others never to do a TSD with a loved one, we had no compatibility problems. Both of us were in pretty good spirits throughout the day. This was probably in large part due to our rally computer. See, the required average speed varied fairly frequently thoughout the stages. But for us, we set the Coralba to display the average speed and simply reset the tripmeter at each change. So I could simply look at the display and see that I was 0.1 mph high, or we could stop and wait until our speed dropped to the ideal level. Normally there would be much work with stopwatches and calculators along with a lot of stress. Our biggest problem was my apparent inability to drive very very slowly at times. We didn't get lost, though. That's the important thing. And any frustration was tempered with humor instead of anger.
We also learned quite a bit about the car. It turned out to be an excellent shakedown test as we'd never spent 12 continuous hours in the car before. First off, both Janel and I found we need more padding in the seats. My memory foam must not be thick enough. Our butts were asleep before we even got to the start line, over an hour from our house. Also, the car is hot and noisy on the highway and cracking the windows seems to draw in exhaust fumes through a number of small holes in the transmission tunnel. The latter is easy to fix. Hot, well, that's probably not going to be a big concern in Newfoundland. Noisy - it's time to look for some transit headsets. We won't be at a sustained 80 mph on the transits, but even the background nose at 40 would get tiring over the course of the day. I'm going to throw some light sound deadening at the back of the car to see if I can help this at all. I think I'm also going to go to a 4.10 rear end instead of my current 4.30, as I don't need such short gearing.
Mechanically, the car was faultless. Some sadistic organizer put a 20-minute stop in at Leadville. That's about 10,000' up, and you should have heard the poor carburetted British cars trying to struggle back to life. Let's hear it for fuel injection!
Okay, almost faultless. The suspension got a nice dirt bath after we spent about half an hour trying to maintain 38 mph on a fairly rough road, and it's creaking badly. I think I just need some bushing lubrication underneath.
A long day, but a good day.
entry 467 - tags: skills, testing, ergonomics, computer, seats | | | June 10, 2008 - Testing results.
The influx of hot air seems to have succumbed to my patching and the car no longer smells like exhaust fumes. So that's good.
The car is much happier with the 4.10 rear end. I've always liked this gearing combination. The stiffer mounts in the differential have cut down on shifter movement and the car shifts very nicely now. So that's an improvement. There should theoretically be an increase in NVH from the new mounts but it's rather hard to tell in this car!
I took the car out to the track again for a few laps, just to see if the rear end was hooking up any differently. And the answer is nope. Maybe a little bit better, but I can still spin up that right inside wheel if I am being aggressive. It takes a turn that's tighter than any that would be used on the street - aka, that would be found in the Targa - but I'm starting to obsess about this a little bit again. On the theory that the car is rolling too much and the rear sway bar just can't deal with this much articulation, I stiffened up the low-speed compression. While the car get a bit happier in transitions (I need to spend more time with this adjustment, as I should be able to really make it pivot nicely) it didn't make a significant difference.
I do really have to thank the guys at the Grand Junction Motor Speedway for working with me and letting me drop in once in a while. When I left today, they were surprised that I'd only taken a half dozen laps!
I'm probably going to swap all the control arms out. The bushings seem to need lubrication again. That's odd, because I've run these sorts of bushings for years in the past without any noise. But that dirt road really seems to have done a number on them and they sound terrible. So the arms have to come out at least partially, so why not experiment? I will check to make sure it's not dry sway bar bushings, which I don't think were very well lubricated on installation. Remember, I installed them at the track and didn't spend a lot of time greasing. Hmm.
edit - I did check, and it is the ungreased front sway bar bushings. Duh. The control arms are fine.
One reason to swap out the arms is because I've managed to accumulate a set of 1999-05 control arms. The rears have only 1700 miles on them so they have nice fresh bushings, while the fronts are higher mileage. The later arms are more heavily reinforced for more strength.
Third, I'm also hoping it'll let me get a little more camber up front, which will allow me to run a smaller (or no) rear bar, which will help with the rear traction.
First, I'll check the cornerweights to see if the right rear is out of whack. The traction problem is not as bad with a passenger, and of course I'll have a passenger during the race! I can tell when I'm going to have problems with the traction, as it's all due to the weight on the right rear wheel. Actually, it's the weight on the right rear and the antics I get up to in order to provoke it.
entry 471 - tags: testing, drivetrain, ergonomics | | | June 17, 2008 - I had the car aligned today.
I had a 9 am appointment and the car went on to the (empty) rack at 10. Sigh. Still, by 11:30 it was all lined up and looks to be a decent job. The right front wheel wouldn't give any more than 1.4 degrees of negative camber, which is a bit of a shame. I was hoping for about 0.5 degrees more. It could very well be my ride height, of course. According to the Spec Miata Constructor's Manual, I should be able to do a bit better. But I know from hanging out with certain Spec racers that it's not unusual for the upper control arm to be accidentally and carefully bent a bit, giving more camber. Good book, by the way.
So, how does it work? I took the car out for a run on my local Targa Simulation Road (assuming the Targa has pinon tree, red rocks and 95F temperatures) and it feels pretty good. The front end sticks beautifully and it puts power down well. Of course, I'll have to take it to the track to see if the low speed, tight radius wheelspin is gone but fast road work is not a concern. I still want to spend a little more time fine-tuning the shocks but I feel the car would be quite competitive at the Targa as it sits.
The new padding for the seats seems to work quite nicely. It wasn't a 2+ hour test, but so far it's an improvement.
I also spent a bit of time tuning the engine with the new cams. They don't like to idle much, but I'm starting to get that under control. The car feels pretty strong and it's adding a whole pile of fuel at 4500 rpm or so - right where the previous cams had a big dip in power, and right where I need a big slug of torque. So far they're promising.
entry 478 - tags: suspension, testing, ergonomics, tuning | | |  | July 28, 2008 - The final high-speed testing took place on Saturday.
In short, the car performed well. I had a brace of sway bars along with me to do some tuning, but it wasn't necessary. The overall balance of the car is pretty good. On long sweepers, it can be balanced on the throttle well. I've set the car up to be a little bit softer on turn-in than I usually do for a track-only car, in order to give myself a little more margin for error. Still, it'll rotate nicely if I set the car up properly on corner entry.
I did play with the ride height a bit to see what that affected. The car's a bit sharper and less prone to understeer at the lower height, which is about the same height that we use for street Miatas at Flyin' Miata. It's easy to adjust so I'll leave that as an adjustment option once we get to Newfoundland.
I tried driving a few different lines around the track to see how the car would react. It's amazing how much slower you get when you're driving like a normal person instead of a racer who knows every little bump in the course. Still, it was good practice and the car was a good tool - mobile and friendly. Even a fast entry into the fastest corner on the track, with a different line than usual, was dealt with well.
The car ran flawlessly and cool despite 30+ minute sessions in brutal heat. I need to spend a bit more time on the dyno to tune the engine but overall it's pretty good. I declared it finished at the track.
Well, finished except for one thing. The tight corners on this track tend to be lefts. There's one relatively tight right hand 180 degree corner, and on that one I could get the inside rear to spin up once in a while if I was brutal on the berms. This was without a passenger, so it probably wouldn't happen on the Targa - but I've decided it's time to solve this problem once and for all. I'll pull the Guru differential out of my Seven and install it in this car. The Guru is a helical-style diff like the Torsen, but with preload so it won't act like an open diff when one wheel loses significant traction. I'll swap that over this week. I'm just trying to decide if I should have it changed to a 4.10 ring and pinion or stick with the 4.30 that's on it already. I do prefer to drive the taller setup, so I'll probably go with that.
The trailer towed really nicely, and when we hit lots of rain on the way home I was happy to think that my little car was safe and sound inside. It's not cheap to tow, but that's life.
entry 504 - tags: testing, suspension | | |  | August 9, 2008 - A great shot from the last trackday at Pueblo.
The car's sitting nicely - this is a fairly fast corner with a quick dab of the brakes on entry, a bit of rotation and then back on the throttle. At least, that's how I do it. And I always exit this corner saying "next time, faster on entry..."
Back to the present day - the diff is in and working nicely. I'll know just how nicely after tomorrow. A surprise track day has come up at the Woody Creek track in Aspen, courtesy of the 25th anniversary gathering of the original quattro. This isn't a track we get a chance to drive very often. It's relatively short but is bumpy in spots and has a couple of challenging corners. I've only been on it once before. I'm going primarily because Janel has to work and because the weather forecast is poor. Hopefully it'll rain. It's not the usual wish for track work, but I don't have much experience in fast driving in the rain and I need the practice!
I have my new race tires all mounted and balanced. If it's rainy, I'll scrub them in and see how full-depth RA1s work in the wet stuff. Quite well by all accounts. If it's damp or dry, I'll use my well-seasoned test tires. I'm also going to drive the car out to see how the new padding works in the seat.
There's a Sport Quattro in attendance at the event. I can't wait to see one in person.
entry 510 - tags: testing, suspension, ergonomics | | |  | August 10, 2008 - In terms of rain, the trackday at Aspen was a failure.
For me, anyhow. One run group of Audis was lucky enough to get wet. I was the only one disappointed, however. Nobody else is any fun.
The day started with a really early morning (8 am driver's meeting and a 2.25 hour drive to the track). The good news? The new foam in the seats makes all the difference. No numb bum at all. That's a big win for the "backsaver" pad from Pegasus racing. Insert glowing testimonial here.
The bad news? The 8 am driver's meeting was at 9:50. My car was given a tech inspection four times. This kinda gives you an idea of the level of organization present. Still, we finally worked out way out to the track. I was staged right behind three Formula Fords that had me a little spooked - Aspen's track is a little on the small side, and I didn't want to accidentally squash one that had sneaked into my mirrors. That wasn't a concern. My biggest problem was trying to get one to give me a point-by. I had the same acceleration, better cornering and vastly better brakes than the driver in front of me, but he apparently didn't have mirrors. After seriously considering using the old "chrome horn" on an open-wheeled car, I ducked into the pits to get some clear track.
The car was okay, but it was hunting for grip. Both ends were skating. I checked the tire pressures and found I had them too high. The next session was better, but still too much hot pressure. Finally things settled down a bit. The car's quite safe right now, giving me lots of warning of what it's about to do. For a track car, I think there's still just a bit too much understeer. Of course, that means it will understeer, even mildly, on occasion. I can throttle steer the car fairly well. But given the unknown nature of most corners in the rally, that's a good setup. In my opinion, anyhow! I'll have the ability to tweak it at the rally if required.
And while it may not have been my preferred setup, a chicane at the fastest part of the track was handled very nicely, a high speed right-left jink that could have been a real problem if the car oversteered too much. Instead, it just screamed right through and surprised a few cars. I was also informed that my lap times were very good for running two-up with a chicane on the straight. Considering my lack of knowledge of this track, I'll take that as an endorsement.
So, despite the lack of rain, a good day. I had fun playing with some purpose-built race cars (who were a little surprised to see how fast this particular Miata could squirt out of corners) and Brandon had an excellent time bonding with his new Locost. Smiles all around.
entry 511 - tags: suspension, ergonomics, testing | | |  | August 18, 2008 - The Flyin' Miata Open House track day was last weekend.
It's always been my plan to have the car finished by this point. Last year, the Open House marked the first track outing of the car. Since then, of course, I've done a whole lot of work!
I'm a little conflicted. The car didn't feel that great to drive, with a soft turn-in and a steady-state cornering balance that was slightly biased towards understeer. Just like last weekend, naturally. This time I had a passenger every time I went out and the car was happier putting down power.
However, the car was fast. Really fast. The fastest Miata out there despite a big power gap.
I was a full 3.230 seconds faster than last year. Granted, everyone was going 1 or 2 seconds faster this year, either due to track conditions or improved cars. But still - over 3 seconds. Some of that is engine, some of it is driver, and the majority of it is setup. I also picked up 0.2 seconds over my time on the same track in April, and the track was fast that day.
I'm going to check the toe on the car and then call it finished. There's another track day next weekend, but I'm going to resist the urge to keep tweaking. It's time to concentrate on final preparation for the race. After all, I have to hit the road in less than three weeks!
One of the other drivers there did note that the fastest Spec Miatas aren't as fun to drive as the slower ones due to their setup. I suspect that I have the same problem. Don't get me wrong, the car is still a lot of fun. The first corner on the track shows off the light weight of the car as the nose dives for the apex, and it's still quite faithful. I've probably given the impression that the car understeers badly, when really it is fairly neutral. Never does the front end wash out on me, and I can always get the back end to step out if I try. A couple of times on the day, I got the rear end out a little too far! So it's a good balance, especially as I'm not a hero rally driver.
entry 512 - tags: testing | | | August 31, 2008 - Remember how I said the weather today was like St John's?
Well, during one heavy burst of rain, I looked at Janel and said "I should take the car out and test it in this weather". She looked back and said "I'll come along". So we buckled in and backed the nice clean car out into the storm.
Unfortunately, traffic was heavy on my Targa Simulation Road and there is absolutely no place to pass on it. So we were stymied going both up and down and didn't get a chance to feel what the RA1s were like in standing water at full chat. But it wasn't without merit. First off, I learned the car is pretty resistant to hydroplaning. I wasn't able to travel too fast (curse the luck) but my best efforts were met with dogged traction. So that's good.
We also got a chance to test the defroster. Finally! It worked a treat on my side, but it blew off one of the ducts on Janel's side and was less than effective. I'd disturbed things when working on the dash light wiring a few weeks ago and never bothered to tape it all back up again properly. It's an easy fix, but an important one. Had it happened in Newfoundland, I would have have had everything needed to fix it in the car with me.
So that's a success then. I'll crawl under the car and see if my new, improved heatshield mounting held up as well - I have high hopes for it. All I did was scrape the undercoating off in that one area so there was smooth metal for the tape to grab, and I know from experience that this tape loves the smooth metal.
It's quite refreshing to be able to spend the day just poking around like this, two weeks before the start of the race. There's no big list of problems to solve or jobs to do. The car's basically ready to load into the trailer. This is very unlike normal racing practices but exactly the way I wanted it. Tomorrow, I think I'll do some painting inside the house.
I've just jinxed myself, I know it.
entry 525 - tags: preparation, testing | | | September 22, 2008 - Over the entire course of the race, the car never surprised me.
Not once. I never had to wrestle with it or deal with wayward behaviour. It simply did what I asked and always gave me an option in case I wanted to do something else.
In short, it was a Miata.
That left me free to concentrate on Janel's instructions and the road. I can't emphasize how important that was - it's why others commented on how smooth we looked. The car simply didn't have any bad habits. More than a year of constant testing and thousands of miles at race speeds in this and other Miatas were a real benefit, as the car's handling is second nature to me and heck, they flatter any driver.
entry 605 - tags: post-race.suspension, testing | | |  | October 15, 2008 - It's hard to believe that it's been a full month since the race.
I haven't just been trying to catch up with my life - although there's been a lot of that. The weekend after returning home, I had the car out on the autocross course again. It was an interesting day, not just because it was rainy and so foggy at times that you couldn't see two gates away. No, it was interesting because of how long it took me to get back into autocross mode again.
During the race, I'd been staying well within the limits of the car because of the consequences of an off. So when I loaned the car to my friend Brandon to see how he would do on the course, it took me the rest of the day to beat him in my own car! I had to get used to dancing the car around closer to the edge of adhesion.
The good news is that he was really impressed with the car's setup and it turns out it does run really nicely in the wet!
entry 633 - tags: testing, skills | | |  | February 21, 2009 - Ever wonder what my Targa Simulation Road looks like?
Very little like Newfoundland, let me tell you. It's not a super-fast road, but it's fun to play on and fairly lightly used. I would recommend driving it slowly first so you get used to the scenery!
entry 656 - tags: testing | | |  | February 21, 2009 - A better look at the surface.
These patches are actually similar to those I remember from Newfoundland, but thinner. Still, it's enough to toss the car around on corners, especially when combined with a number of creases and lumps. In the winter, this road gets a fair bit of grit poured on it so it's a nice substitute for the gravel that gets thrown on to the roads in the race. Plus it's only a few minutes from my house!
I was up on the TSR testing a couple of video cameras. One is a cool little unit called the Motorsport Hero that comes with a suction cup and a fisheye lens. I'll put some of the results online - it's really fun to play with. The other is a cheap HD unit I picked up that records to SD cards. Unfortunately, while the video quality is okay, the sound quality is abysmal. The car is simply too loud for it. I'll have to see what I can do about that.
The car's working well. I'm pretty happy with how the suspension is working. It's going to be so much fun to get it back to sea level where it'll see a 20% power increase.
entry 657 - tags: testing, video | | | March 6, 2009 - I spent the afternoon at the local track, playing with the car.
It wasn't a completely satisfying day, as I was having trouble getting the handling just the way I wanted it with the stiffer springs. I'm really torn as to whether I should use the current setup or the Targa setup at Laguna Seca in a couple of weeks. Really, I need the extra stiffness for the track. And I probably could have used it in Newfoundland as well. I'll probably take it as-is and then stick the extra springs in the truck for a Saturday evening change if desired.
My biggest problem was getting the balance right. I think if I put the thinnest rear sway in my collection in the rear, that will do the job. The car was a little tail-happy with the current 14mm bar hooked up. My lap times were inconsistent, with a fastest of about 1:05.2 - a half-second slower than at the Open House just before the race. An ambient temperature in the 50s instead of in the 90s may be a contributor, as is the fact that the track isn't getting used much at all in the winter. I did spend a bunch of time trying to get that right rear wheel to hook up on corner exit. Again. Not liable to be a problem at Laguna though.
Janel took the wheel for a bit. She's not a huge fan of driving the car, it turns out. She's happier in the navigator's seat. The Targa car is just a bit overwhelming. The amount of information was a bit of an overload and the car was just too responsive. Her turbo Miata (which I compared to the race car back in August) is a little softer and a little mellower. Everything happens a bit more slowly and gradually, and that's more to her liking. At least, right now it is.
At one point, she was back in "her" seat watching my feet to see how I heel-toed on downshifting. She didn't feel the need to look up at all, as she was totally relaxed despite the fact that we were circulating the track fairly quickly. This is the result of the Targa.
And on a similar note, I have to say the Targa has spoiled me. I've got hundreds of laps at this track. I know it pretty well. And today it was all just kinda blah. The same dozen corners, over and over again. After you've come over a blind crest at 100 mph with your foot pinned to the floor because your navigator says it's clear, or changed your approach mid-corner because there's gravel at the apex, circulating around the same track over and over just doesn't carry a thrill. I'm sure it would be different if I was running wheel-to-wheel with someone, but we have to get back to the Targa. Janel feels the same.
entry 659 - tags: testing, suspension | | | March 25, 2009 - A great weekend at Laguna Seca.
I drove out to California expecting a two-day track event, and ended up with quite a bit more than that.
Of course, there was a big track event. The Targa car spent around 7 hours on the track. I was playing with the fast guys in the A group. The open passing and chance to play tag with some of my friends in close company made the track far more interesting. Partway through the first day, circulating alone, I was sick of the same 11 corners over and over. But once I got into a chase with a few others, it added a whole new dimension. I can see how wheel-to-wheel racing could be addictive, although it's a different sort of game from the open road. I did notice that my peak speed on the track was only about 160 km/h.
During the Targa, our top speed on the Leading Tickles stage was 190 km/h. With trees and rock walls lining a bumpy road that we'd never seen before.
In the rain.
The car was handling perfectly. I'd nailed the balance with the new springs and sway settings, and I didn't touch the setup all weekend. When my good friend - and ex-pro driver - Rick Weldon took the wheel, he came in laughing and completely in love with the car. He didn't want me to change a single thing. It's good to get his stamp of approval, as it's always a bit worrisome to think that maybe I've adapted to the car instead of getting the car right. He really felt the car was prepared well and the handling was bang-on. Another fast driver commented on how it was impossible to get the car upset. No matter what I did, the car just ate it up and came back for more. Naturally, this seemed to be in context of my habit of making full use of the berms. "The track is wider for that car", one other driver noted. The hearty engine came in handy as well, even holding off at least one turbo Miata down the long front straight. Rick went out with Tom Matano in the passenger's seat of my car and got into a big scrap with one of his Spec buddies, everyone coming in with big grins.
Janel was also there, getting friendly with the driver's seat on the car. It was the first time she's really had the car up to temp and she was much happier than she had been at our little kart track day a few weeks back. As soon as she discovered how well the brakes worked, she started using them in earnest - she's always had the habit of coasting up to corners, so that's a big step. And more importantly, she discovered that all that information coming from the car is useful. As she described it to someone else - her Miata will do the same thing whether she takes a corner well or takes it badly, but not tell her. But the Targa car will let her know if she takes a corner well, giving her the feedback to improve. She can feel the tires working. She figured out turn 10 almost immediately, and I worked with her over the weekend to take what she was doing on that corner and apply it to others on the track. We worked our way around piece by piece - 6, then 4, then 5. It turns out she likes fast corners best. The Corkscrew wasn't her favorite as she had to muster the nerve to go over that blind drop. On her last session, she went out with Rick and he managed to coach her best driving ever out of her, including figuring out the Corkscrew. She was overjoyed and Rick was bubbling over with praise about how well she takes instruction. She's got a good feel for the car, and after this weekend I think she likes the driver's seat almost as much as the navigator's! She was nervous that Rick would be disappointed, but it was the exact opposite. Was I proud? Oh yes.
The only downer to the weekend was that, in a remarkable and extended spasm of incompetency on the part of US Air, she arrived 24 hours late and our planned mini-vacation in Monterey didn't happen. We'll be avoiding that airline in the future.
There were lots of fans of the Targa car there. I don't think Janel ever believed me about how many people know about the car and followed our race, but she got a chance to see the enthusiasm first-hand. Thanks to everyone who came up to introduce themselves! I was also surprised at the banquet on Saturday night when I was honored with an award for my contributions to the Miata community. Wow!
The car saw about 7 hours of track time. It was almost perfect, with only a couple of hitches. The first happened when Rick was driving the car, the check engine light came on and the car lost power. That's the Hydra Nemesis dropping back to the safe spark map to protect the engine. I haven't been able to figure out just what happened there, although the fuel level was getting low. I tossed in a bit of gas and some toluene (causing some real confusion in the pits, seeing as how I was pouring it out of a paint shop can) but the problem happened again. A full tank of 91 "competition" fuel and it cleared up. Weird. I'm going to change the fuel filter, as I don't know what's gone through that tank with all the small Newfoundland stations. Then, in the last couple of sessions, the high-rpm stumble from the last day of the Targa came back. Again with the puzzling problems! I'm going to brainstorm this one with my coworkers for a while and see what they say.
I also got the chance to drive Elvis, the LS1-powered Miata I autocrossed a few months back, on the track. Yee hah. The thunderous rampage down the straights was to be expected, but on top of that the rest of the car worked very well. It put down power far better than it had any right to do, and the overall balance was still very good. As it should be, because Elvis was running the AFCO suspension developed on the Targa Miata! When another car pointed us by, we didn't just pass them. We evaporated them. It would be an awesome Targa weapon, with huge acceleration, a wide powerband and the ability to dance in the twisty bits. Unfortunately, it got coolant into the cylinders and the car got parked. The current theory is that the modified heads were ported too far and got into a coolant passage. Whops.
Now, Elvis had been driven to California while I towed the Targa car out. So, other than a quick stop to change to street rubber in Reno (after going over a 7500' snowy pass on race rubber alone at 11 pm!), I drove the race car home without changing a thing. 7 hours on the track, 17 hours on the interstate. I've always said that a good Targa car was a good street car, but I never thought I'd have to prove it in this way. I averaged 30 mpg and 70 mph on the run from Sacramento to Reno, which is nothing to be be ashamed of. How's that for a dual-purpose machine?
entry 663 - tags: Laguna, skills, testing, handling | | | August 5, 2009 - I pulled the suspension out today to install some upgraded bits and pieces.
Nothing major, just detail stuff. At the same time, I reinstalled the "rally springs", the 375/300 combo we ran in the Targa. I've got some different bumpstops installed and we're running a slightly higher ride height, so let's see how this works. I do enjoy the fluidity the car gains with this softer setup, but will I miss it on the track?
Well, I'll find out on Friday. The Flyin' Miata Open House (now called Summer Camp) is this weekend, and I'll be running yet another track day as part of it. The FM staff aren't allowed to run transponders to prevent us from all chasing the lap record (again), but I'll put the Traqmate data acquisition system in and see what interesting stuff pops loose.
entry 687 - tags: suspension, testing | | | November 2, 2009 - Track day time!
The new 750/450 springs worked quite well, pretty much eliminating body movement but allowing the suspension to still soak up those berms in the chicane. The car was fairly quick as well, allowing me to match my best-ever time of 1:04.7 despite a cold day and slow times for most people. Janel also liked it, posting a personal best and getting down into the 1:10 range. She's not a big fan of the feel of cold race tires on the warmup lap. There was actually ice on the start/finish line when we arrived in the morning, I'm not exaggerating about the cold!
The shocks are dealing very well with the rates, even keeping the car comfortable on the street. It's lost that very smooth ride it had for the Targa, of course. Bumps are dealt with without upsetting the car, but it doesn't seem to repave the road the way it did. I'm still playing around with what the best spring setup for the race would be in the event that we get to go back. 450/375 and some good ride height? Probably. For track use, these heavy springs are obviously the way to go.
entry 716 - tags: suspension, testing | | |  | February 26, 2010 - Time for a new intake test!
This particular one is designed for a 1994-97 head. Well, I have a 1999-05 head. The ports are the same shape, but they're higher in the head on my setup. Usually this involves cutting and welding the manifold to move stud holes.
This very cool adapter comes to the rescue! Bolt it to the head with counter-sunk screws, then slip the manifold on. It needs just a little bit of porting to be a perfect match, but I'll do that if the intake shows promise.
entry 726 - tags: intake, testing | | |  | February 26, 2010 - That's starting to look like a race engine.
It took a fair bit of work to get to this point - I spent all day Wednesday as well as a couple of hours on Thursday and Friday - but I've added at least 50 visual horsepower.
The biggest problem was a fuel rail that had holes 10.50mm in diameter. The stock Miata rail is 11.00mm. I couldn't get the injectors to seat without tearing an o-ring. I tried various o-rings from the shelves at Flyin' Miata, but all they had were stock or oversize. A trip to NAPA yielded the perfect thing - injector seals from a Geo Metro! Kudos to the NAPA counter guy who nailed them on the first try.
The red lines are running to a mount for the idle speed control valve. This gives the throttle bodies a bit more civility than you often find with this sort of setup. The ones on the Seven don't have this, and I have to keep that car alive with the throttle until the engine warms up. Not here!
I haven't had it on the dyno yet, I'm hoping to do that this weekend. On a short test drive, the car ran very rich on partial throttle, but felt very good wide open. I'll sort that out in the Hydra programming. It makes a very characteristic noise, with a distinct growl for each cylinder. The return springs on the throttles are pretty stiff so that will take some practice when matching revs - but overall, considering the amount of work to install, it behaved pretty well.
I'm looking forward to see what this has (or hasn't) done to the power output.
entry 728 - tags: intake, testing | | |  | March 28, 2010 - Here's a before-after peek at the wide angle lens, taken up on the Targa Simulation Road.
I think I need to move the camera up a bit in the car, but the wider field of view helps a lot with the sensation of speed. My other concern with the camera had been the lack of image stabilization, but that's not a problem. In fact, the video was rock steady even on this very bumpy road. So that's a big winner then. I'll post the video soon - that's another advantage to the Flip. Very easy to post video to various hosting sites.
I was up on the Simulation Road to see how the new dual-spring suspension worked. Pretty well, I have to say. After a couple of stops to set the shocks (it never ceases to amaze me at how one click makes the difference between "hmm, it's okay but not great" and "wow!") the car seemed pretty happy. This is a tough stretch of pavement and the car was certainly pitching, but it was stable and well-connected to the road. I doubt it would have worked as well if I'd been running the main spring rates alone - 650 and 425 lbs, I think. That's a lot of spring! I'll take it out on the highway later today to see how stable it feels at speed without the massive headwind and with the shocks set up.
entry 735 - tags: video, suspension, testing | | |  | March 28, 2010 - Time for some more dyno testing!
One nice thing about the individual throttle body setups is that I can change out the air horns and alter the intake runner length. In theory, a short runner should trade off low rpm torque to gain high rpm power - and a long one should do the opposite. But if they're way off, then you just plain lose. Since I have a collection of horns, I'll simply do some back-to-back testing and see what happens. It's always interesting to simply install a pipe that's 1" longer and see a power bump.
I had the chance a while back to talk with Bill Schenker, a national-level CSP autocross competitor about his engine. It makes very good horsepower - similar peak power to my engine, but with less torque - and it's all come from hundreds of dyno runs, testing one slight change against another. One thing he told me was that the length of the intake tube running from the stock intake manifold to the filter had a big effect. Again, a 1" change made a notable difference. Of course, he was talking about naturally aspirated power so it wasn't a 15 hp difference, but if you can find 10 places to gain 1.5 hp, there's your 15 hp gain.
So, bring on the air horns!
entry 736 - tags: testing, intake, air horns, IRTB | | | March 29, 2010 - Another new video.
This is a run up the Targa Simulation Road to test both the springs and the video camera. I'm pretty happy with both. We'll see how the springs do on-track this weekend.
Video
entry 739 - tags: video, testing, suspension, video | | | April 4, 2010 - No pictures of the new intake yet, but I have track videos!
Fastest lap
Smoother fast lap
The track day went pretty well. It was a fairly cold one and I only got about three sessions in the Targa car (along with the chance to drive a 350Z, a BMW M Coupe and a couple of FM Miatas), but my best time was a 1:04.959. That's about 0.2 seconds off my best in the car, nothing to be ashamed of. There was a time when simply dropping below 1:06 in any car was unusual!
The dual spring setup does allow for some body roll, but the lap times would indicate the car isn't suffering too badly. It absorbed the berms well and was very stable under braking. I'm trying to decide if I want to keep this setup for Laguna Seca or if I want to pull the secondary springs so the car corners flatter and has quicker reflexes. Tough call. If it can still hustle around our little autocross track here this quickly, I'm thinking the dual setup is working.
The engine felt good. For the first time, I noticed a lack of pick-up coming out of one of the hairpins at 4000 rpm - that's the dip in the torque curve. The heavier throttle pedal (due to a stiffer spring) took a little getting used to in order to be smooth, but I adapted pretty quickly. Nobody noticed that the car was particularly loud, so I'm hoping that's good for Laguna Seca sound levels. Hoping hoping hoping. I did have one person ask me if it was a V8 because it didn't sound like a four-cylinder!
Pictures of the intake are at work, I'll put them up tomorrow.
entry 742 - tags: video, GJMS, testing, track, IRTB | | | September 5, 2010 - Track day test!
The good news? The new diff works beautifully. I could get on the power much earlier and get a solid drive off turns - left and right. It's a clutch-type diff. I had an idea this might be effective as the V8 cars from Flyin' Miata have shown an uncanny ability to hook up out of corners. On the first session, I managed a 1:03.796. That's nearly a full second off my personal best in the car. Now that is some serious progress!
It wasn't without a cost, however. I found the handling of the car was difficult. In particular, I had trouble with corner entry understeer. It didn't seem to be there for that first session, but almost seemed to get worse as the day went on. I tried to drive around it and I tried to tune around it with shock settings and a stiffer rear sway. Interestingly, the sway bar change didn't seem to have any effect. I also found I couldn't get enough rear bias into the brakes - even with the rears turned up all the way, I'd still lock up the fronts too easily.
I suspect what might have happened is that the old tires have finally given up. This is the same rubber I ran in the Targa almost exactly two years ago. They've seen 5 days at Laguna Seca with two drivers, probably a dozen track days on this track, some road use and of course the Targa itself. When the Seven is too low on traction, it gets a similar behavior. Oddly, the car doesn't feel slippery, it's just not hooking up the front under braking or turn-in. Am I going in the wrong direction? Hard to say. I might just have been trying too hard.
I have another track day on a big track next weekend, and I flat-spotted at least one of the fronts badly enough that it's done now. I have two more mounted tires and two unmounted ones in the garage. Both pairs from the Targa (or possibly pre-Targa testing) of course, but they haven't seen as many heat cycles. So I'll swap the flat spotted front tires out for the "new" unmounted ones and put the other pair on the rear, then take the existing rears with me as spares. I'm also going to double-check that front shock to make sure it's working as well as bleed the brake system again, and if things aren't any better then I might throw in some extra front camber if possible.
I ended the day a bit bummed out that I couldn't go faster, but I'm feeling a bit better now that I look at the times again. Another Miata at the event - a turbo car running some Nitto 225/45-15 tires on 15x9 rubber!- was putting down times right around the same as I, and his times fell off over the day like mine did.
Was the diff a success? Well, if I can sort out the handling, yes. Right now, the car wouldn't be happy on the Targa because it's too easy to wash out the front end, but if I can get that sorted then it's a real winner in terms of fast corner exit speeds.
entry 761 - tags: testing, differential | | |
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THE DIARY