For those that have been to road course, what kind of HOT pressures are you running?

I've been keeping mine to about 40-42psi hot. I've gone as high as 56 because I wasn't paying attention.

 

What type of tire and size are they?

 

It's in my sig, 245/40/18 Yokohama AVS S1.

 

It depends on the tires and the size, naturally. IIRC on Kumho V700's in 235/40/17, one of the guys here runs around 40~42psi hot in front. Not sure about the back.

 

You're right where you need to be for front tires air pressure... I like 42-45psi hot in the fronts, and depending on the track and expected speeds, I may match the fronts for good turn in but with the trade-off being increased tail-happiness or drop them by 3-5psi compared to the fronts and get more traction.

A few things that can affect your selection in dialing the car's handling on the track: (keep in mind the Maxima has a weight distribution of approximately 64% Front, 36% Rear. FWD !@#!$@ )
* Adjusting tire pressure.
* Adjusting the Stillen RSB. (if available)
* Adjusting stiffness of struts. (if available)

 

Yeah I typically keep the rears 2 psi lower then the fronts. The car is fairly neutral on the track but the back gets a little skittish under heavy breaking at highspeed.

But now that I have my JICs that should go away, but now I have the added complexity of playing with ride height, preload and rebound.

Too bad I lve up here in Canada, I have two track days left and will have to wait until spring to continue tuning my car.

 

to tell you the truth I don't even know what kind of pressure I'm running at the track, but the best advice that I could give you is to buy a lazer temperature sensor, that's the best tool to figure out where your pressure should be, you want to measure the inside/middle/outside of the tread and from that you want to determine the "right" pressure

1) if the middle temp is high, then you have too much pressure
2) if the both outsides are too high, then you have too little pressure
3) if one side is really hot, you're screwed, hehe, just kidding

but that's the general trend, you want to see where the temperature of the tires are and then go from there, there is no right/wrong pressures, it's different every time, even +/- 5F would make a difference. you just have to adjust it as soon as you get off the track for the next session

 

[QUOTE]Originally posted by Vinipux
[B]
but the best advice that I could give you is to buy a lazer temperature sensor, that's the best tool to figure out where your pressure should be

A word of advice on the infared types of pyrometers. Have a friend take the temps IMMEDIATELY after the run. I've been told for every 100' driven (back to a grid/paddock) and not running the temps can drop 10%. Also temps underneath the tread are higher than the surface. Probe type pyro's are better for really analyzing the setup. I use the infrared type myself - it's better than nothing

 

[QUOTE]Originally posted by BEJAY1
[B]hmmm... I have both, so maybe I should try using both, yeah, sorry not mensionning that you have to test the temp right away. and also, with infared, you can always aim between the grooves, unless you have all season tires, which you shouldn't race on, usually you can get to the "underneath" layer

 

- Don't waste your money on a pyrometer. Just take some shoe-polish and make three or so lines along the sidewall and into the first part of the tread. Run a lap or two, then come in and check to see how much polish is left.

- If you are over-cooking it, or your tires are under-inflated, you will be able to see the rollover. If you've got too much pressure or are just babying it, then there will still be a lot of polish left near the tread.

- This is a tried and trusted method that just about everyone in the SCCA uses. Pyrometers are only worth it if you are trying to win a national championship or if you are driving a real race car. Chances are that you are not doing either - otherwise you would not be in a Maxima.

 

That only tells you if you're rolling em over. Nothing about understeer, oversteer, weight shifts, or alignment problems.