Tire pressures and trophies
Early runs were hampered by overinflated tires
Got to test out the new tires today at the IndySCCA Auto-X in Indianapolis, however the day did not go without its problems. With a strict time constraint on the location we were only given 4 runs each, and I wasted 3 runs because it turns out the tire pressure gauge I was using was reading pressures 8psi too low (i.e. 44psi showed as 36psi on the gauge!). So for 3 runs I was running pressures in the low/mid 40s (psi) front and rear, resulting in quite a significant loss of grip. Even with the tire pressures way off the summer tires offer a significant improvement on grip levels and response.
Final run, tire pressures set to at least the right ballpark
On the final run I borrowed an accurate pressure gauge, set the pressures to 35psi front, 36psi rear and went for it, basically not really having any baseline setting except previous auto-x where I have had more luck running slightly lower front pressures (albeit on different tires). The car suffered from some oversteer on the final run, however I was still able to shave over a full second off the time from run #3. Looks like I need to invest in a better tire gauge… Best run today: 32.871. With a few more runs and some tweaking of the tire pressures I believe I could have cracked into the 31 second range.
Once again there were no other E-Stock cars running, so I ended up on the day with the trophy for the ES class. Hopefully more to come with some competition next time.
My first trophy (considering I didn't claim the trophy at the last event)
Thanks to Justin for grabbing pics of the car in motion. Hopefully you’ll run your WRX next time around!
Edit: Instead of posting a track map I found a video posted from a E46 M3 driver on his run: http://vimeo.com/6143126
August 17th, 2009 at 01:37
Very nice. Why the headlights up? Wanted the car to look happy on your runs? Haha
August 17th, 2009 at 07:46
Advice from an experienced Miata guy who said that it was up to 25deg cooler at the intake with the headlights up.
August 17th, 2009 at 11:19
What about all that draggggggg?
Jk
August 17th, 2009 at 11:58
Interesting about the headlights.
235$ left, less 50 or so for a tire guage…what’s left? Anything?
August 17th, 2009 at 14:37
I’m just going to use my other cheap ‘stick’ tire pressure gauge that I have in the DD for now. At least it’s more accurate than this dial gauge. Just did a test to compare both: Pulled a reading of 22psi using the dial gauge, 34 psi on the stick gauge. What a piece of shit.
As for budget-wise I’m looking at an alignment job soon (~$120) and an oil change before the trackday in October (~$30). I’ll take the brake pads out and check the caliper pins/apply some more lithium grease, but I already have the necessary stuff for that. Maybe I’ll buy myself a nice torque wrench and 21mm socket for the wheels so I can stop borrowing everyone else’s.