Race cars in
AO Silver Member
Join Date: Oct 2007
Location: South Africa
Well done on a great day out.
Correct brake pads are very important - EBC Yellows worked nicely for me too, I don't think green will cut it, I am now on ENDLESS race grade pads which is better - even for street use (yes my racer is street legal).
I gained a second on coil-overs (stiffer springs and MUCH higher damping).
When it comes to tire sizing - I would like to agree to Speedmaster, but semi's rubber for 17" is nearly more than double the price - so I will not buy that and cannot comment. The difference between 15" and 16" is there, but not a full second. Biggest issue is look at sidewall thickness / flex. So in essence lower the profile...
On tire pressure - use a temperature gauge to decide - this can also help with camber adjustment decisions. If the center is hotter than the edge, drop a good psi, maybe two for 5deg C. If the outside run hotter than inside, you can increase (neg) camber.
In my 2.0TS I run cold pressure 2bar front and 1.8bar rear which increases to 2.3bar hot front and 2bar rear. Camber is set to -2.5deg front and -2deg rear and my inside edges run just hotter that outside edge and full range of tire surface scrubs, no grain.
Just double check the tire if it was the tire itself graining, or you just pickup a lot of rubber ONTO tire (off race line) and check the mag dish (behind spokes) - I have found lumps of rubber shoots up and get stuck there, throwing balance off.