What tire pressure should I have?

[///M Power]

recommended is 33 front and 36 rear

i have 17x8.5 w/ 235/40

spirited driving

[kyle_baker]

Originally Posted by ///M Power

recommended is 33 front and 36 rear

i have 17x8.5 w/ 235/40

spirited driving

is that recommended for all tire sizes in general for our cars or just those with same measurements as yours?

thanks

[4evrwyntr]

I'll say - 33 + 36 looks like you're keeping it a touch low for grip purposes. I thought the set was 35 and 40 psi front/back respectively?

[Furious]

there is a way to calculate from the max tire pressure, something like max -10 psi, but normally i use around 32-34 front and back depends on what kinda day i wanna have.

[mmclaren]

my pirelli's on a 17/225/45 have a max psi of 51 i usually run 45 check on ur tyres and have it to suit ur driving

[Cruzin 323is]

Originally Posted by mmclaren

my pirelli's on a 17/225/45 have a max psi of 51 i usually run 45 check on ur tyres and have it to suit ur driving

wow u have a 45 inch rim huh??? and your profile, is HUGE also.

[4evrwyntr]

Originally Posted by Cruzin 323is

wow u have a 45 inch rim huh??? and your profile, is HUGE also.

Silly. Those are 17's. Or did I miss sarcasm.
45 sounds a bit high? Even on max load...

[///M Power]

My door jam says recommended 33 psi front and 36 psi rears. But thats with factory wheels and tires.

I dont want any super uneven wear. Any recomendations for spirited driving?

[4evrwyntr]

Strange... you have a 92-95, right? OBDI? Those don't have the staggered wheels? I wonder if that makes a difference...

I could have sworn mine said 30-35 front 35-40 rear.
If you're going to drive "Spirited" you want to underinflate by around 4 psi. But that's ... well... like REALLY spirited (unless things have changed?!?). Also, you don't want to underinflate too much ... I dunno. I just wouldn't. It would make me feel uncomfortable on something with a large sidewall to underinflate so much (stress on the weak part of the tire) - but you're in something with real low profile, so I wouldn't worry too much. Unless you're riding Kumhos or something.

I'll shut up now.

[green325is]

on my '94 325is Sport pkg, door jam says FT 28 and R 32. BMW dealer told me 32 and 34. So??? I think I will try 30 / 32. I've got 16" oem wheels.

[theruss1an1]

If you look at your tire and where the tread begins there are little dots all the way around. After you take corners fast you get those wear marks, if those wear marks begin where the dots are you are fine, if not you have to adjust the air presure. I had my tires 235-40-17 at something like 30 psi on a track day, but they got warm on the track so Id say they were at around 32 psi (the presure goes up in heat and comes down in cold right, correct me if Im wrong) but my wear marks were just around the dots.

-Serge

[///M Power]

P1 x V1 / T1 = P2 x V2 / T2

Volume remains constant. Temperature increase from T1 to T2. P2 pressure increases. Yes, basica chemistry says you are correct Serge.

[mmclaren]

225/45/17
and i will get a photo Pirelli p6000's Max pressure 51 PSI

[4evrwyntr]

p6000's? How are those going for you? I heard bad things about those wheels... maybe there's a new variant or something.

Maybe the side walls are really weak and need extra support or something?

[mmclaren]

side walls come with a warrently supposable
i use continental sports on the front"rate these very highly"
and the p6000's on the rear

tyre pressure on ur door is for stock tyres...