i have khumo ecsta supra's and i was wondering what a good psi for around 60 degree weather.

 

I doubt you'll see much difference in traction changing the rear tire pressure on street tires. I would inflate the front tires to 40 psi to reduce rolling resistance.

 

it depends on how the track is hooking on that night. its something you have to play with, just like launch rpm.

 

radials are a whole different thing than slicks, they require more air pressure to hook up. I've had success in the past running 30psi in the rear. And like the other guy said, run as much as possible in the front.

 

Hey, someone else not brain-washed by the old theory of "drop the air pressure!" .

With street (radial) tires, often times (but not always) deflating them can be counter-productive. I've tried dropping the pressure from ~30, to ~25, to ~20, and had negative results, or simply no benefits at all. However, last season I started pumping the back tires upto ~35 psi before running, and I cut as low as a 1.92 60' time on my STREET TIRES!!! (beat the 1.96 I got with BFG drag radials! ). My tires are Hankooks (can't remember the model, sorry.....but stock 245/50/16's).

 

Exactly like what said...

Bump up the pressure in the fronts.

and in the rears start high and dip a little but no too much.


I run 30-35 psi on average on street radials I try to keep as high as possible.


If you are like some and drop the pressure ot like 20 psi, the middle of the tire is bowing up and only the outer edges are gripping, you are getting worse traction... lowe the temp, then lay down a patch of rubber you will see 2 stripes on the outside and the center empty.