tyre pressures for track

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oldspa
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tyre pressures for track

Post by oldspa » Sun Jun 28, 2015 4:45 pm

998 Imp steel panels, CR 65 4.50 x M 13 tyres. What pressures would you recommend for a first track outing :?: . I realise the views will vary but just as a rough ball park figure as I am totally in the dark... Imp006

Many thanks,

Keith
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Re: tyre pressures for track

Post by Adrian » Sun Jul 19, 2015 9:36 am

Hi,
I run the same tires and use 28psi for rears and 18psi for the fronts on a 6" rim and I have used the same pressures on 5.5 wide rims too.

Cheers
Adrian
Last edited by Adrian on Mon Jul 20, 2015 8:46 am, edited 1 time in total.
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bazzateer
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Re: tyre pressures for track

Post by bazzateer » Sun Jul 19, 2015 10:16 am

Adrian wrote:Hi,
I use 28psi for rears and 18psi for the fronts on a 6" rim and I have used the same pressures on 5.5 wide rims too.

Cheers
Adrian
That's what I run on the road with my 185-60-13s on 6" rims. I thought on track you're supposed to run higher pressures???
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Re: tyre pressures for track

Post by The Nun » Sun Jul 19, 2015 10:47 am

You can get it spot on by experimenting, costs a bit though.
Too low a pressure the outsides of the tread wears before the centre, too high and the centre wears before the outsides, so try in between the two and by the 3rd set of tyres you will have got it right. :)
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Re: tyre pressures for track

Post by SimonBenoy » Sun Jul 19, 2015 11:36 am

Peter,

The same is true of temperatures, by using an infra red temp gauge, you can measure the temperature at different places on the tread and adjust pressures accordingly until they are reasonably close.

Bazz - race cars ought to be lighter than road cars and we also use cross plies which seem to tolerate quite a range of pressures with little variation in handling.

Thanks - Simon
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Re: tyre pressures for track

Post by Lotus-e-Clan » Sun Jul 19, 2015 9:05 pm

To give you an alternative ball park range ...

I use 22- 24 psi for 205/55/13 AVON CR500 rears and 16 psi for 175/55/13 AVON CR500 fronts on a Clan.

CR500s are sticky soft rubber road /track tyres with a fast wear rate of 20 (versus about 200-300 for normal road tyres) - but they seem to wear reasonable slowly on the Clan.

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Re: tyre pressures for track

Post by SimonBenoy » Mon Jul 20, 2015 10:47 am

So the CR500s don't actually have anything in common with Dunlop CR65s apart from the colour :lol: :lol:
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Re: tyre pressures for track

Post by Lotus-e-Clan » Mon Jul 20, 2015 11:10 am

SimonBenoy wrote:So the CR500s don't actually have anything in common with Dunlop CR65s apart from the colour :lol: :lol:
And the CR bit ...but good point. :lol:

'Ti's a shame CR500s aren't used more on Imps - 'cos handling/grip wise they feel really secure on the Clan - I think the rear 205s affect acceleration just a tad mind -
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