I'm running 245/40/17's on the stock wheels, my current tire pressure is 32 in the front and 29 in the rear. My cousin ( drives a WRX) told me it's too low for tires that size. What should my tire pressure be with these size tires? This is a daily driver car, never will see the track.

Thanks!

 

I'd run at least 35 pounds to support the car weight properly. Up from there will help increase handling and steering response.

 

What do you guys think about 36 in the front and 34 in the rear?

 

36 is fine but I'd like to see that all around to keep load capacity where it needs to be. You wont feel the diff in two lbs split, so I'd run 36 all around.

 

Thanks a lot for the advise bro! I'm going to go to my friends shop tonight and adjust the tire pressure to 36 all around. Should I go any higher than that or is 36 all around perfect for the streets?

 

Np Anything over 36 will help handling but stiffen ride. So I'd start at 36 and see what that does for ya. If you want to tighten it up add a couple and drive it again.

 

I was reading the owner's manual, the tire pressure goes up as the tire temp goes up, if you are running 36 lb won't the tire be over inflated?

 

The rule of thumb is for every 10° Fahrenheit change in air temperature, your tire's inflation pressure will change by about 1 psi (up with higher temperatures and down with lower).

We evaluated the affects of heat generated by the tire's flexing during use. We tried to eliminate the variable conditions we might encounter on the road by conducting this test using our "competition tire heat cycling service" that rolls the tires under load against the machine's rollers to simulate real world driving. We monitored the changes in tire pressure in 5-minute intervals. The test tires were inflated to 15 psi, 20 psi, 25 psi and 30 psi. Running them all under the same load, the air pressure in all of the tires went up about 1 psi during every 5 minutes of use for the first 20 minutes of operation. Then the air pressures stabilized, typically gaining no more than 1 psi of additional pressure during the next 20 minutes.