Recommended tire pressure (cold) for Pirelli 285/30 & 225/40 18's please?
#1
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Thread Starter
Recommended tire pressure (cold) for Pirelli 285/30 & 225/40 18's please?
First time I've owned these tires so need a little guidance.
TIA
TIA
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#8
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I run 35 psi front and 41 psi rear measured cold in the AM in my garage. I too think the 44psi in the rear is on the high side. I have recorded 44psi rear cold, then driven not that hard/fast and the temps went up to 52psi meausred about 30 seconds after I stopped. I have chalked my tires a few times and found that 41 psi works best around here in the summer. Other parts of the world will most likely need different pressures due simply because it never gets super hot here in the summer. Chalk your tires and see what happens... It's certainly an educational exercise.
PS I read some tire pressure info in the tech section of the PCA web site and found some interesting data regarding tire pressures and tire wear. Interesting stuff especially considering some of the advice went against "common knowledge" about pressures. Check it out...
PS I read some tire pressure info in the tech section of the PCA web site and found some interesting data regarding tire pressures and tire wear. Interesting stuff especially considering some of the advice went against "common knowledge" about pressures. Check it out...
#11
Rennlist Member
For a few weeks... lol. It rarely goes over 85 degrees F. Try the tire chalking theres a good chapter in Bruce Andersons Porsche Performance Handbook on tires/wheels/suspension, etc. Where it mentions chalking. Also, look at the staggering lengths F1 teams go to with tire pressures. different temps/conditions warrant different pressures. By the way we're virtually 1/2 to the north pole from the equator here. The summers are lovely, the winters are the exact opposite but I have never had a better car in the snow (with Blizzaks of course) than my C4, the traction is immense. People look at me like I'm nuts (especially those in sport ute's or even better in WRX's/Evo's) driving it in the winter, then I take off with virtually no slip/wheelspin and pull away like a scalded cat.
Originally Posted by Ritter
Do you actually get summer that far North ?? I kid- must be really lovely. But low 80's not low 90's like here?
#12
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Porsche recommends that 36/44 F/R tyre pressure combo for the the US and for Europe. Is it to minimise heat build-up due to sidewall flex at a sustained 150+ mph?
#13
Rennlist Member
The way I look at it, depends on the type of driving you do. If you just drive slow in city speed limits then the low pressure is fine for comfort but if you aggressive or like high speeds then the higher pressures are for you. I'm in South Florida so it's extra hot on the streets. Tire temp can go off the scale.
The day I bought my car the back tires had less than 20lbs in them! I nearly lost it coming off a turnpike exit. it had Zero grip on wet. Lucky for me I have 30 years of snow and ice driving, I could have easily destroyed the car in the first 15 minutes of ownership. Pressures are very important, on my sporbike I never would leave home without checking them. I my 993 I check weekly. I almost lost a good friend last year because of low front tire pressure. He tried a slight turn at high speed and the bike slammed him into a wall. I run 36F 41R Works for me. Chris
The day I bought my car the back tires had less than 20lbs in them! I nearly lost it coming off a turnpike exit. it had Zero grip on wet. Lucky for me I have 30 years of snow and ice driving, I could have easily destroyed the car in the first 15 minutes of ownership. Pressures are very important, on my sporbike I never would leave home without checking them. I my 993 I check weekly. I almost lost a good friend last year because of low front tire pressure. He tried a slight turn at high speed and the bike slammed him into a wall. I run 36F 41R Works for me. Chris
#14
I run 36/44. Mainly cause it is what Porsche tire manufacture recommend. I have lowered the pressure a couple of times to 32/40 and got a better ride as do not push car anywhere to max on the street. However, my car can sit for a couple of weeks, and rather keep the standard 36/44 to avoid flat spots.
#15
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Thread Starter
Thanks- I'll experiment a bit. I ran it hard y'day and had 36/38- the back end felt a bit soft.
Will try 44 and work betwen the too. Does sound hard though.
Will try 44 and work betwen the too. Does sound hard though.