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But if its too low what will the tread pattern ware be?

So i'll start off at 32 psi?

Or better to start of centre 35psi?

I can't do damage can i?

If they are under inflated, then the outsides will wear out quicker

If they are over inflated, then the middle will wear out quicker

Personally I would try 30 psi cold, as in first thing in the morning, in the garage, before it moves.

Cheers

Gary

i got 17/235's i think and i run 43psi in the front, 41psi at the back.

I'd back that off a bit man, seems very high unless the tyres you have are made to be run that high :P

I normally run between 35-38psi, if someone can tell me they can feel a difference of a couple of psi on the street they are full of shit.

personally I like very high pressures for spirited drivng on street tyres. 36-38 cold. even with low profiles tyes, the improvement in handling is worth the increased harshness to me :P

I hate to ask the newbie question, but I assume you would normally run lower pressures on the track?

I ran the usual street pressures, about 38psi on 17/9/45 (factory rims) tyres on the track and handling was excellent, one of the instructors thought I was running semi-slicks :P

For an R33 GTR is that too high for the track?

But is it bad for the tyre? It was my first track day so I wasn't sure what I should/should not have been running.

personally I like very high pressures for spirited drivng on street tyres. 36-38 cold. even with low profiles tyes, the improvement in handling is worth the increased harshness to me :P

depends, i only really run sports tyres with stiff sidewalls so i dont worry too much about sideways flex, sure its there, but if the tyre pressures are too high i get terrible grip. i changed my RE070's from 38psi to 28psi, and the change in grip was amazing, i didnt notice a whole lot more sidewall movement, just the amount of extra grip was amazing. they were a 225/45 mounted onto a 17x8.5, so very mild stretch. i dont worry about tyre wear on the road, i change tyres that much that i rarely get a chance to see any noticeable wear caused from driving around on the roads, so its hard to go by that.

I hate to ask the newbie question, but I assume you would normally run lower pressures on the track?

I ran the usual street pressures, about 38psi on 17/9/45 (factory rims) tyres on the track and handling was excellent, one of the instructors thought I was running semi-slicks :P

For an R33 GTR is that too high for the track?

But is it bad for the tyre? It was my first track day so I wasn't sure what I should/should not have been running.

well on the track u are driving a lot harder and building up more heat in the tyres, so there is a larger pressure change in them from the servo, to you driving at full speed.

hmm well i did start at 35-38psi when i bought the car....

then i read max 51psi n im like shit better crank up this mofo...

but since general consensus here is 35-38psi.....i might switch back!:)

well on the track u are driving a lot harder and building up more heat in the tyres, so there is a larger pressure change in them from the servo, to you driving at full speed.

I've also heard that having higher pressures means less sidewall flex and less heat built up (or should I say less quickly)?

Anyway, thanks for the opinion.

I've also heard that having higher pressures means less sidewall flex and less heat built up (or should I say less quickly)?

Anyway, thanks for the opinion.

yeh it will reduce sidewall flex, but its all about sacrifices, and a decent semi slick will have more rigid sidewalls and stop a lot of sidewall flex.

and yes, that sounds about right with the higher pressure and less heat build up, but id say that would be to do with the extra friction and all with a lower pressure tyre, its this that gives you grip though. so i guess its a trade off.

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