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The other thing is to prepare your head. Go out here to have fun, but don't forget that you'll be driving really fast, so concentrate. Don't try and go flat out from the first lap, ease into it.

Keep an eye out for what the other people are doing. Be smooth(or drift if that's what you are there for!)

Regards, Andrew.

I can add another thing from my debacle today at Wakefield - either be 1000% sure that your brake pads will survive the day, or take a spare set. Pads for a skyline are surprisingly hard to find in Goulburn on the weekend...

Guest Impul 25T
Originally posted by red900ss

I disagree.

Tyres should be inflated 2-4 psi more than normal road pressure. The reason you are getting a "4-6 psi rate of expansion" is the tyre flexing excessively and heating up. This in turn heats the air which then expands and the pressure increases.

Running too low pressure reduces tyre life and increases the chance of damage to the tyre/wheels if you hit a ripple strip.

just my $0.02 :(

Are you talking street tyres or track tyres?

You do realise that a hot tyre is stickier than a cold tyre? You are trying to get that expansion, created by heat, to warm up the tread surface of the tyre. If you start to high, you won't get the right temperature increase in the tyres, and they won't get improved grip. An example, a mate's GTR on the track, running semi slicks, started out with a tyre pressure of close to 38psi cold, car skated around when the tyres warmed up. Dropped the pressure to 34 cold, next time out the car stuck like glue to the track once the tyres had warmed up. If you start at almost 40psi, when your tyres get heat into them and the pressure increases, does that not mean that you are more likely to run on the centre of your tyre..... causing undue wear?

Have any of you heard of drivers like Stuart Owers, Ray Williams? They say the same thing as I have just said, as has Sadistic Rage. I would tend to believe them, firstly, because they have been racing for over 15-20 years, and they are pretty good, ie, NZ champions in their respective classes on numerous occasions.

I am talking street tyres sorry if I didn't make that clear. Semi-slicks and race tyres are a different thing all together.

Street tyres DO NOT need to warm up like race tyres do. Different rubber compounds.

"You do realise that a hot tyre is stickier than a cold tyre?"

yep. Do you realise Street tyres warm quickly to their operating temperature and the temperature variation from "cold" to "hot" has much less effect on their level of grip when compared to a track tyre?

" You are trying to get that expansion, created by heat, to warm up the tread surface of the tyre. "

umm, sorry don't get what you mean by the expansion warming the tread?

I run my Dunlop FM901s at 37 psi front, 38 psi rear. I can tell you as that this is the correct pressure for my car etc. Many slicks typically run at around 22 psi.

I don't claim to know everything, far from it, but I know what I know. If in doubt talk to someone who sells tyres for track work (NOT your local tyre place :P ).

red900ss

Try 44psi front 45psi rear it might surprise you.... thats for the race track.... NOT the street or dragstrip.

37 and 38 would be typical pressures for an interstate trip or normal street if you tend to push things

Guest Impul 25T
Originally posted by red900ss

Do you realise Street tyres warm quickly to their operating temperature and the temperature variation from "cold" to "hot" has much less effect on their level of grip when compared to a track tyre?

" You are trying to get that expansion, created by heat, to warm up the tread surface of the tyre. "

umm, sorry don't get what you mean by the expansion warming the tread?

I run my Dunlop FM901s at 37 psi  front, 38 psi rear. I can tell you as that this is the correct pressure for my car etc. Many slicks typically run at around 22 psi.

I don't claim to know everything, far from it, but I know what I know. If in doubt talk to someone who sells tyres for track work (NOT your local tyre place :cool: ). [/b]

Sorry, when it was said for Track prep, I just assumed that slicks were involved.

The second part also refers to a slick, sorry, bad wording. The point I was trying to make is as the inside air tmp increases, it warms up the tread by convection.

I run my 901's at pretty much the same pressure also, and the last bit, definately ask someone who actually knows and has had experiance. Most local tyre shops pretend to know but don't really.

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