Thread: Tire pressure?
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      12-29-2019, 04:47 PM   #16
Prissy
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Drives: M340i
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2015 BMW F30  [5.50]
2020 M340I  [0.00]
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2008 BMW E92  [9.00]
2010 BMW E92  [10.00]
Quote:
Originally Posted by alpinewhite3 View Post
Quote:
Originally Posted by Prissy View Post
RWD

Thanks bro. I am gonna give that a try.

My 330i is RWD (225/45/18 all season Pirelli P7 Cinturato runflats all around) and door jam recommends 32 front 38 rear.

Tried the following combos:

32F/38R: Steering felt heavier but it didn't feel as quick or crisp. Grip was great and tires did not squeal under hard cornering as much. Felt like I could take corners fairly hard without worrying about oversteer. I felt like i would know well before i pushed the grip limit. This is why BMW recommends this pressure. Their #1 goal is safety and preventing oversteer/spin outs is more important than steering feel.

38F/38R: Steering felt a bit quicker and turn in was crisp and quick. Great steering feel but I felt like i sacrificed some grip b/c of the added front pressure(less contact patch up front) Tires squealed more under hard cornering and could sense an oversteer situation possible without much warning or notice. Also-car felt darty at high speeds bc of the crisp steering/smaller contact patch of front tires.

35F/38R: This is why i ultimately settled on. Seemed like the best compromise of steering feel and grip. Steering was not too crisp but not too lazy either and car felt grippy and still less likely to go into an uncontrolled oversteer situation without an adequate warning.


Anyway, hope this helps. There is no magic perfect pressure combo. It really depends on what you prefer and are looking for in terms of grip was steering feel. That being said-i would avoid going above 38 psi in any tire. Car will be too bouncy/darty and you will sacrifice a lot of grip.

Let me know what worked best for you. Like others have said, staggered set up should not really matter when it comes to pressure front/rear. And as always-make sure you set the pressure on cold tires. (havent been driven on for at least 3-4 hours)
Quote:
Originally Posted by alpinewhite3 View Post
Quote:
Originally Posted by Prissy View Post
RWD

Thanks bro. I am gonna give that a try.

My 330i is RWD (225/45/18 all season Pirelli P7 Cinturato runflats all around) and door jam recommends 32 front 38 rear.

Tried the following combos:

32F/38R: Steering felt heavier but it didn't feel as quick or crisp. Grip was great and tires did not squeal under hard cornering as much. Felt like I could take corners fairly hard without worrying about oversteer. I felt like i would know well before i pushed the grip limit. This is why BMW recommends this pressure. Their #1 goal is safety and preventing oversteer/spin outs is more important than steering feel.

38F/38R: Steering felt a bit quicker and turn in was crisp and quick. Great steering feel but I felt like i sacrificed some grip b/c of the added front pressure(less contact patch up front) Tires squealed more under hard cornering and could sense an oversteer situation possible without much warning or notice. Also-car felt darty at high speeds bc of the crisp steering/smaller contact patch of front tires.

35F/38R: This is why i ultimately settled on. Seemed like the best compromise of steering feel and grip. Steering was not too crisp but not too lazy either and car felt grippy and still less likely to go into an uncontrolled oversteer situation without an adequate warning.


Anyway, hope this helps. There is no magic perfect pressure combo. It really depends on what you prefer and are looking for in terms of grip was steering feel. That being said-i would avoid going above 38 psi in any tire. Car will be too bouncy/darty and you will sacrifice a lot of grip.

Let me know what worked best for you. Like others have said, staggered set up should not really matter when it comes to pressure front/rear. And as always-make sure you set the pressure on cold tires. (havent been driven on for at least 3-4 hours)
Looks like 330 and 340 doesn't share the same pressures (see my label). I had the same tire set up as you before I swapped the rears to wider.

Right now I am at 38 fronts and 40 rears and it rides pretty good. I might test 38f/42r and I will report back in case someone's interested.

I also believe the Pirelli Cinturatos P7 RFTs are trash to begin with.
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