I just installed a set of Sumitomo HTR Z 225/50s on my 16X7.5" K1s. They look great, but I'm uncertain what psi I should run? Max cold inflation is 44psi, but the Maxima is a very car for 225/50s and 44psi is way too extreme. I'm running currently running the fronts at 34 and 31 in the rear. The ride is good and pretty quiet. I'm just afraid 31psi may be too low.


Dave

 

I run 34/31 in 225 50 16 BF goodrich V rated Comp TA tires (they smoke well) on the stock 6.5" SE rims. Since I have stock rims, when I get new tires, I'll go to 215 55 16 because it looks ridiculous with the edges buldging out cause of the narrow rim.

 

I would put nothing less then 32psi in each tire. I usually run 35psi all around on my 225/50/16 BFG's. I have had no problems with improper tire wear-the tread is nice and even.

 

you guys do know that the Nissan recommended tire pressure is 32 front 29 rear don't you?

 

Careful Bri - this came up before and different year 4th gens and models had slightly different recommended pressures.

P.S. Running 225/55/16 this Sunday. 55/38 was a bit high last year.

 

Running higher pressure in the fronts helps correct the FWD understeer. In both 215/55-16 and 235/45-17 I've run anywhere from 6-8 lbs. difference (anwhere from 36/30 to 38/28 f/r) and the back end lines up better. Autocrossing was more like 50/34.

 

In my Dunlop 225/50-16 SP8000's, I run 40/30 on the autocross track; 30/30 around town and 34/34 for long highway trips.

 

A bit off topic, but does it help if you inflate the rear tires to a higher psi when racing at a 1/4 mile track? Let say have the front tires at 22-25psi and rear at 35-40psi?

 

People say it does help a little bit when you run higher pressure in the rear tires. Pretty much, hardcore drag racers do everything possible, every little thing counts to them. With more air in the rear tires, it suppose to have less rolling resistance since there is less of a contact patch of the tire with the ground.

 

Hm...interesting. It didn't helped me last time. Strangely my best run to date was when I had 35psi on all four tire. And that was on the crappy stock Goodyear RSA's. Who knows. I think I will try maybe 25psi for the front and keep the rear at 35psi to see how I'll do. I'm running on Bridgestone RE950's on my stock 15" rim.

 

Here's info from Roger Kraus Racing. Click "Oversteer/Understeer Correction Sheet" under Tech Sheets.