What tyre pressures do you use?

[peanut]

I'm curious to know as I confess I rarely check mine. Some tyre manufacturers recommend uping the pressures by 3-4 lbs if driving predominantly at motorway speeds. How about you trackday guys ? some of the classic GT cars on Sky were running 42lbs !

 

[sawood12]

I rarely check mine also but I currently have a slow leak on one tyre so now check weekly. I'm currently using 32 psi at the rear and 30psi at the front. I can't envisage ever putting as much as 42 psi in under any circumstances. That just feels way way too high for a car tyre. Can't say i've ever found my car to be particularly sensitive to tyre pressures.

 

[peanut]

42lbs were for racecar tyres I shouldn't imagine you'd run anything higher than 36lbs on the road but I'm curious to see what other use.

 

[appletonn]

After a little experimentation, I've settled on 34 front and rear. The make and type of tyre will obviously influence your choice of pressures too[]

 

[stevespic]

I run 32psi front and rear for normal every day driving.

 

[sawood12]

Wow, that surprises me. 42 psi would surely make the middle 3/4 of the tyre bulge out therefore reducding grip, and once the tyres saw a few hard laps the pressure would be more like 48 psi. Oh well I suppose it is one of those things that is down to personal preferences.

 

[peanut]

these GT racers are really old classics with modern 10" wide slick tyres. They were racing on Sky today again. Fascinating film actually.

 

[George Elliott]

I tried running 33psi on the left and 32psi on the right.
This helped compensate for the road camber, - except when overtaking when it was worse, - so now its 33 all round.
George

944t
964

 

[sawood12]

ORIGINAL: peanut

these GT racers are really old classics with modern 10" wide slick tyres. They were racing on Sky today again. Fascinating film actually.

I was watching that today as well. What a fantastic way to spend your time and money.... if you are a multi millionaire that is. Just brilliant. Great to see these old classics being used as intended - and they are not exactly treating the cars with kids gloves either. Some of those old timers really mean business.

 

[psi]

Finally settled on 33 all round.

 

[poprock]

Factory settings vary across the 944 model range. Does anyone have an idea of why?

The Lux manual recommends that the fronts are softer than the rears (my memory is fuzzy but I think it was 26psi and 32psi), whereas the Turbo manual says to go with 36psi all round.

 

[Diver944]

ORIGINAL: poprock

Factory settings vary across the 944 model range. Does anyone have an idea of why?

Different tyre sizes and profiles, increase in weight over the years and a massive performance increase would be my guess. Porsches original 250 Turbo pressures were 36 all round on 16" wheels, but after 1989 they increased this to 44psi on the rear []

We can only guess this was because of some high speed blowouts in Germany after sustained 160mph cruising - pure speculation, but the lawsuit era was just begining in the 90's

I run 32F and 34R with my 17" wheels and it promotes even wear and a supple ride. 44psi rear would be like a balloon for ordinary driving

 

[zcacogp]

Interesting .... 36 all 'round on my S2 (D90's in standard size.)


Oli.

 

[TK2015]

32 front and rear on the 17" Goodyear F1's
28 front and rear on the 16" for the track

 

[Alpine]

32 psi all round on my D90s

 

[333pg333]

There's no way that you'd pump track tyres up to 42psi unless perhaps they were some copies of old style tyres that had different properties. If anything you drop pressure down to the low to mid 20's and wait for them to come up to low to mid 30's. Maybe they got to 42psi hot, but even then that's very high.

 

[944Turbo]

Saw the programme as well and that was hot temp,
Tony