[s-cars] future of awd and TT handling

[colin cohen]

So we tried a number of different tire pressure combinations on the TT while 
racing it in the SCCA T3 National event two weeks ago.  I got stymied on 
qualification and in one of the races by failure of first one and then 
another of the spark plug power packs but here is what we did learn.

Softening the front shocks (rebound and compression) helped front end grip 
measurably as did higher rear tire pressures.  On one session I measured a 
hot pressure of 42 having started at 38 and a fairly even cross tire temp 
starting at 150 on the inside and declining to 135 on the outside.  This is 
consitant with the rear camber and a lot higher ( ambient was 75) then I 
have seen in recent events indicating that I am sliding the rear a little. 
The fronts were also mid 40s although we started cold at 33, with temps at 
170 plus - very much in the zone for Hoosiers.

Note I am running an asymmetrical wheel tire combo too with 17" 235s on the 
rear and 16" 240s up front.  My times were 2 or 3 seconds better than my 
last run but Don Istook was able to effect the same improvement with just 
the softer shocks.  The only corner that upset the ECU (limp mode until the 
wheel was straight and I got off the gas) was a slow 300 degree hairpin. 
Fortunately the track out exit is so wide that I was able to adapt my 
technique to take the corner in 2 phases, getting on the gas only in the 
second phase where the steering wheel had very little turn.  But it was the 
long way around and this offset the torque advantage I would have otherwise 
enjoyed over the Honda S2000 and RX8s in the class.

So thanks for the help everybody.

Colin