NON ITR related tyre pressure help

[Jingers]

Any round abouts on what you expect 14" semis run interms of tyre pressure?

30? I know for each individual application it varies but if someone can provide me with a starting point it will be greatly appreciated.

[fatboyz39]

For track, i usually keep mine at 28-30psi on all four corner on 13'. Just remember those pressure are when HOT. Always check the tyre pressure immediately after a session.

[Jingers]

are there any relationships between say smaller alloys?

smaller alloys run less pressure? 28-30 hot is lke what 24-25 cold?

[fatboyz39]

i think there is a relationship between tyre profile? well you wouldn't drive on 24 psi when cold. Lower the tyre pressure at the track.

For street driving i leave it at 32 psi.

[j0nbubz]

sorry to crash the thread - but word on appropriate street tyre pressure for 17" 215/45?

Thanks

[Chosta]

i run 38psi (hot) front, and 34psi (hot) back for 17" 215/45.
I've been running 34-34 before but i get uneven wear upfront(more wear on the outside of the tyre than inside).

It's safer to run under-inflated than over-inflated.

[3r1k]

Why do you run more pressure on the front ?

Sorry for the offtopic.

[Chosta]

cause the majority of the weight of the car is at the front (70:30 ratio i think).

[3r1k]

Say my pressure is 32 COLD, what it will be when it's hot?

[Chosta]

i dont know. I've never pumped when cold. but i heard it increases by 2psi from cold to hot.

[3r1k]

Well i'm running 225/45/17 so I assume I can follow your foot step? 38 psi hot at front and 34 psi hot at the rear.

I'm running 33 hot all around

[JCE]

Jing,

Is this for street or track use?

For street use, 32 psi should be fine.
Unless you are doing some pretty hard driving on the street I dont think you will be able to raise the temperature significantly.

Try 32 psi cold, go for a drive and see how it feels (ie sidewall flex etc), then take the hot temperature and see how much it varies to adjust your cold temp accordingly.

I think tyre pressure is a very subjective topic, I like to run higher than 32 psi in my tyres. Although you sacrifice outright grip I find you gain more feel through the tyre and less sidewall flex.

I personally like my cars to rotate more so I generally run 1-3 more psi in the rear.

If this is for track use, search about using a tyre pyrometer to find the ideal pressure.