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38 for dry, 36 for wet. Thats fairly safe.
If anything, you should run higher pressure in the wet - the theory is it holds the tread "open" better so the tread drains water better.

Generally, the tyre manufacturer will have a recommended tyre pressure - check the manufacturer's spec sheet for your tyres. Then, on a RWD, add 2psi to the fronts.

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thanks guys, I have set my tyres to 36psi all around.

Forget all the rest - try 32 front /30 rear.........Guaranteed best pressures for tyre life & moderate ride/ handling compromise. These the sphincter of the universes running 40psi must have shares in tyre companies because that will wear down the centre tread quicker than Alan Moffat's GTHO !!!!!!!!! :happy:

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I usually run my 245x35x19's between 40-42psi. I was told by my tyre place to run a minumum of 40psi for 19's. I bought second hand rims and two of the tyres had heaps of little cracks on the inside sidewalls. They said this was due to insufficient pressure. The pressures being run by most of you I would consider fine for 18's but I thought the lower the profile of your tyre the higher the pressure you'd need to run.

I have some K104's on the rear and found this on their website.

'Generally, the optimum inflation pressure is about 90% of the maximum level. For high-speed driving, drivers are recommended to use a higher than normal pressure.'

Unfortunately my car is in the shop so I can't check to see what the maximum should be according to this.

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If anything, you should run higher pressure in the wet - the theory is it holds the tread "open" better so the tread drains water better.

Generally, the tyre manufacturer will have a recommended tyre pressure - check the manufacturer's spec sheet for your tyres. Then, on a RWD, add 2psi to the fronts.

the main reason for running a higher pressure in the wet is that the tyres will heat up quicker than running a lower pressure...

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  • 2 weeks later...

checked my tyre pressure today and the fronts were at 46psi!!! and the rears on 38psi. i got 19s put on about a month ago( assuming 'they' would put it at a allround level). proves that if you get new tyres or rims put on,, always check the pressure yourself after you leave. or tell the tyre fitter what you want, then still check it for yourself. prob the reason why i often find understeer in the wet.

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if you use low profile tyres, then u need higher psi. less sidewall requires higher pressure.

so standard 16's are prob ok with 32-34psi. but 18/35's or 19/30's need about 38-40psi.

Thankyou, someone who finally knows what they are talking about! I cant believe so many of you post up so much shit in such a simple topic, this is like the extreme basics even my mum knows. As munky said the pressure you should run in your tyres all depends on what profile they are. Find out what tyres you have and what size and do some research if you want an exact pressure to pump them up to, different manafacturers have different recomendations. As for wet and dry conditions it so makes no difference. Only time you might let them down a bit is when your on the track and they are getting the chance to get some heat in them.

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thanks guys, I have set my tyres to 36psi all around.

I run Bridgestone GIII's and they tell me 36 psi is the best for all tyres but like mentioned different brands different pressures as well as each owns opinion.

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