Tyre Preasure Question

[aussieboxy]

I've just replced my standard 16" with 18" and have 245 x 45 on the fron & 285 x 35 on the rear. Any suggestions on preassures?

Thanks

[edevlin]

On the recommendation of several others on the forum, I have been running higher than the factory suggested pressures to good effect. I think I have settled on 34/39 for front/rear for normal driving, it seems to give better control on the twisties with my PS2's.

Ed

[Cloudsurfer]

I agree with running somewhat higher pressures to help handling, though be careful, esp at the rear with overinflating and getting uneven wear.

As to your tire sizes, you are running too high an overall diameter. If you want a 285 rear, it needs to be a 30 series, not 35 series. Most run a 225/40 front, if you wanted a 245 (which is quite wide for the front of these cars) it would need to be a 35 series to have the proper diameter (which would then be a bit too small overall, but is still closer to correct than the 45 series).

Patrick

[Frank Patrick]

Since many Boxsters are running on summer spec tires, won,t this overinflation have a negative effect on the tire longevity?

[Topless]

Originally Posted by Frank Patrick

Since many Boxsters are running on summer spec tires, won,t this overinflation have a negative effect on the tire longevity?

Higher tire pressures within reason tend to wear the tire more towards the center. Boxter tires usually wear at the edges... Inside edge for daily drivers/freeway riders, outside edge for canyon carvers/track hounds. I tend to wear em out on the outside even with max negative camber. A little extra air can be a good thing.

[racer_d]

For the stock 225 front, 265 rear on 18's, porsche lists 29psi front and 36psi rear. If you want to dial out some additional understeer, you might try 36 all around.

[clb0099]

I have 205/50WR-17 on the front wheels and 255/40ZR on the rear ones. What should be my tire pressure?