Targa Miata
MIATA BUILD
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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.
tags: suspension