UKKid35

I'm at the Nurburgring, the conditions are that the track surface is wet, and not getting to dry out much if at all.

I have standard S4 slots with ContiSports at the front and Toyo Proxes at the back, I have been running at factory spec of 37/43. This is not working at all, I have no grip at the rear whatsoever. The car is startard trim, not lightened in any way and loaded with half a tank of fuel and two adults totalling 300 lbs.

I'm going to try 37/37 for the next couple of laps. What pressures should I be using?

mark kibort

oh gosh, drop it down to 30-32psi as a starting point. i remember a day where an entire NSX group was running spec pressures and all of the novice drivers were spinning constantly. when i asked the pressures, they said , " we are all running 45psi hot" needless to say, they took my obvious advice and no one was spinning after that!.
dont expect much heat if its wet out. thats left for the real racing rain tires.

the fact that its wet, would point to even lower pressures too!

MK

Dennis K

Tires vary. I've run:

Michelin Pilots @ 32f/30r psi hot
Pirelli P-Zero Corsas @ 38f/36r psi hot
Michelin Pilot Sport Cup @ 36f/34r psi hot

After a dry track session, I usually have an 8 psi gain from cold pressures to hot. In the wet they may gain only 2 psi or so. The factory spec of 44 psi cold rear is crazy.

GlenL

Take Mark's advice. It's much better to start soft and work up than to have tires that are too hard and lose grip at unfortunate times.

The worst case is that the tires are heating, and becoming harder, while the driver is getting more comfortable and aggressive. He's losing grip while asking for more.

Starting at 30psi is good. If you've got grip but think the handling is vague or sloppy then add 1 or 2 psi. And take off a psi or 2 if handling is stiff but grip is lacking.

UKKid35

Thanks guys, I did two more wet laps with 37/37 before reading your replies, then later dropped the pressure further to 33/33. It was definitely an improvement with 37/37, but by the time I took it to 33/33 I decided to drive only when the track was dry. I had seen too many very expensive incidents, not to mention a few moments when I thought I was going to join those with unwelcome souvenirs from the track. Apart from anything else I wasn't sure I could afford the Armco charges: a Ferrari 355 driver who did this sort of damage to his car
http://www.wreckedexotics.com/355/35...0510_001.shtml
also ended up with a bill for $3000 for the track damage, which I saw him pay as I was handing over the cash to pay for my laps.