| MIATA BUILD |
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 | |  | August 9, 2007 - A lot of little jobs got done on the car tonight.
The most obvious underhood is the installation of the red valve cover - that's an instant 15 hp gain for sure, although I need to get a filter for that cam cover breather. I installed an interior rear view mirror, the plastic cowl at the base of the windshield, cleaned up a bit of wiring, changed the throttle cable bracket and generally did a few small things on the car.
The Mazdaspeed MX-5 turbo muffler sounded terrible, so it's been replaced by a Flyin' Miata part instead. That sounds a lot better and also drops a few pounds. I also determined that my recent addition of a no-slip patch was a total failure, as it started to creep around the footwell and announced itself to be a hazard. So it's gone now although the bits on the pedals remain.
The car's heading for the alignment shop tomorrow morning and then on to the dyno to get the engine into shape. It's part of the push for the track debut at the Flyin' Miata open house.
entry 281 - tags: ergonomics, exhaust, alignment, engine | | | August 13, 2007 - Car gallery added to the website.
After being innundated with a request, I've put up a gallery of the car from a bunch of angles. Yes, it's completely self-indulgent. But I don't mind at all.
So, if you'd like a Targa Miata wallpaper or just want the chance to critique the stripes carefully yourself, check it out: Targa Miata gallery.
Meanwhile, the car got aligned today. A bit of tuning on the computer and it's ready for the track. I've been driving it around for the last few days. I'll post some driving impressions soon.
entry 290 - tags: alignment | | |  | September 28, 2007 - Sway bar time!
I have a good selection on hand. For the front, a 23mm front bar from a Mazdaspeed MX-5, a 7/8" adjustable aftermarket bar and a 1" adjustable. The rear will be served with a 14mm Mazdaspeed bar or a 5/8" adjustable. I'm trying a different setup than I usually use to ensure the rear wheels stay hooked up on rough surfaces. We'll see how this works out. I might see if my local alignment shop is willing to work with me on this, I expect it'll be spending a lot of time on the rack.
entry 318 - tags: suspension, alignment | | |  | November 1, 2007 - The reworked shocks are here.
These shocks are the ones I expect to use for the Targa. They're made by AFCO, a US company that has experience in both road and dirt track racing. They're pretty exotic and have a number of features designed for maximum durability and traction. I've been hugely impressed in dealing with AFCO so far, having a number of long discussions with the engineers about the damping, stroke and bumpstop design. These shocks will become part of the Flyin' Miata lineup, and they are definitely a custom item built to the Miata's needs.
The new shocks are quite a bit different than in their original configuration. For example, the fronts have a 2" longer body. After installing the original set, I made a number of measurements and sent them off to AFCO. From this, just about every component of the shocks was changed - the upper hats were shortened, the bodies changed in length and the shafts altered. Now I have the exact travel range I requested. I can also run the car a bit higher than I did before - not something that other Miatas will necessarily want, but it'll give me the ability to absorb all sorts of rough surfaces. Eric wants me to jack the car up to Paris-Dakar levels, but that might be a bit extreme.
One nice side effect is that they're also easier to install. Not that this is a critical aspect of shock design, but I sure appreciated it when it came time to put them in.
Today I'll cornerweight the car, then get it aligned. I'm experimenting with alignment settings that are closer to those used in Spec Miata, unlike the street-biased ones I've used in the past. The testing on Saturday will be used to determine how it works.
entry 331 - tags: suspension, alignment | | |  | November 1, 2007 - Cornerweight time.
This wasn't a very serious cornerweight session, as I'll be taking the suspension apart before too long. I mostly wanted to make sure there weren't any really major problems, and to set the ride height.
The car's fairly tall, as fast Miatas go. It's about 13.5" front and rear, although I need to recheck that after driving it home tonight.
The real question is - what does it weigh? A quick disclaimer first, I always weigh cars with a full tank of gas. Not in this case, because I forgot to fill up on the way in to the shop this morning. The car is showing 3/4" on the gauge. I'll fill it up on the way home and then add the weight of the fuel so I can get a good, comparable number.
Anyhow, with the 3/4 tank, the car came in at 2080 lbs. Not bad! It's nose-heavy, with 53.1% of the weight on the front wheels. That's okay, I'll have more weight in the trunk during the race and the occupant weight lands more on the rear than the front. I'm pretty happy with that. My target weight was 2070 lbs wet, and I'm pretty darn close.
update: it took almost exactly 4 gallons to fill the tank. At 6 lbs/gallon, that means the car is just a hair over 2100 lbs with a full tank. The final choice of sway bars will affect this, as will the installation of the rally computer - but it's a good start.
entry 332 - tags: alignment, weight loss | | | November 2, 2007 - Alignment time.
I'm trying a new alignment on this car (because I'm not trying enough other new things!) that has a fair bit of negative camber up front. I was aiming for about 2 degrees. Unfortunately, the right front wheel refused to cooperate, and the alignment tech was only able to get 1.2 degrees. Not what I was looking for! Part of this is due to my relatively high ride height, but the left front didn't have any trouble. So I'll be inspecting that area of the suspension later for problems. It didn't show up the last time the car was on the rack because I was aiming for far less negative camber and I had a lower ride height. It is odd, though, when I had the car on the lift yesterday I checked all the cams and they all appeared to have a lot of adjustment left.
The resulting setup has about the same camber front and rear while I had been planning on a slight front bias. I hope my collection of sway bars will allow me to make the car handle reasonably well. It doesn't really matter much, though, as I'm going to have to test all over again once I find my missing camber. Sigh. At least I'll be able to spend some more time on shock settings, the rest of the testing won't tell me much. Instead of a test session, it's going to be more of a play session. It's a shame, I don't have another opportunity at this track until May and it's a fairly major expedition to get there.
entry 333 - tags: alignment | | |  | November 12, 2007 - This wheel used to have about 1.5 degrees of negative camber.
Now, it has none. A quick check with the toe plates indicates close to an inch of toe-out. Once I'd pulled the shocks out again (they're going in a street car for final evaluation as a Flyin' Miata product), I also pulled out the lower control arm on this wheel. Yup, looks like a crease in the top. That would explain the alignment problems.
Honestly, after bending a wheel like that, I'd be shocked if the control arm hadn't bent. They're intended to be the weak point in the suspension, absorbing the punishment to protect components like the subframe. I'll stick another control arm in, that's an easy fix.
entry 339 - tags: suspension, alignment, crash | | |
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