Tyre Pressures
- Thread starter Guest
- Start date
Diver944
Active member
I asked the same question on some 968 forums when I first had 17" s fitted as they had 17' s as standard on the Club Sport with sports suspension, but got little definite info. I was hoping a 968 manual would have it stated.
Other 944 owners with 17" ' s have recommended 32-34 psi front and 34-36 rear which I have followed for about 10,000 miles now with even tread wear all round
Other 944 owners with 17" ' s have recommended 32-34 psi front and 34-36 rear which I have followed for about 10,000 miles now with even tread wear all round
For tyre pressures phone specific manufacturer and they will have a tech dept to advise. Tell them the type of usage..fast road, track days etc. Run tyres just above recommended psi and check pressures after each session when tyres are hot. Drop pressures gradually as it is easier to let air out than it is to get it back in...you have to blow really hard!
So many different factors come into play. Ambient temperature. Track temp. Your driving style etc. New tyres should not be thrashed because they will need to cure. Thrash them and trash them so ideally do not fit just before going out on track. Ideally change just after track day ends and run new tyres in. For road use go by handbok to start with and raise/lower by a few psi to find best for you. Handbook is normally suitable for most road applications.[
]
So many different factors come into play. Ambient temperature. Track temp. Your driving style etc. New tyres should not be thrashed because they will need to cure. Thrash them and trash them so ideally do not fit just before going out on track. Ideally change just after track day ends and run new tyres in. For road use go by handbok to start with and raise/lower by a few psi to find best for you. Handbook is normally suitable for most road applications.[
]
Robbiemeister
Member
Paul
When I checked Dunlop' s (I think) website they quoted the same pressure for all the 968' s as the later 944' s. 36psi all round if I remember correctly.
When I checked Dunlop' s (I think) website they quoted the same pressure for all the 968' s as the later 944' s. 36psi all round if I remember correctly.
Diver944
Active member
It's a funny one this Slim. On the cars with 16" wheels as standard (Turbo and S2) the manual and petrol flap up until 1990 states 36 psi front and rear. From 1990 onward the manual and petrol flap states 36 front and 44 rear. I followed this on my '90 S2 for the first year I had it and the rear always felt 'loose' and noisy. Then I noticed I was getting excess wear in the centre of my rears.
After much discussion with other owners on www.titanic.co.uk/944 I reduced my rears to 36 psi and the car felt much better and 40,000 miles later I have not had excess wear in the middle of the rear. When I bought my '89 Turbo last year, sure enough it stated 36 all round????
I don't know the reason why the change but 944 owners 'legend' tends to agree that it was raised to counteract possible high speed (140mph +) blowouts on German Autobahns. Normally I would always, always say follow the manufactureres guideline but in this case I just cannot agree. 44 psi is way too high (unless you are planning any Autobahn trips [] )
After much discussion with other owners on www.titanic.co.uk/944 I reduced my rears to 36 psi and the car felt much better and 40,000 miles later I have not had excess wear in the middle of the rear. When I bought my '89 Turbo last year, sure enough it stated 36 all round????
I don't know the reason why the change but 944 owners 'legend' tends to agree that it was raised to counteract possible high speed (140mph +) blowouts on German Autobahns. Normally I would always, always say follow the manufactureres guideline but in this case I just cannot agree. 44 psi is way too high (unless you are planning any Autobahn trips [
] )
Well don't rev it to 5K and dump the clutch then
Many manufacturers recommend higher tyre pressures for high speeds or heavy loading, perhaps Porsche opted for 44lbs as a catch all situation. High tyre wear in the middle of the tyre would demonstrate over inflation so 36lbs does seem to be the best route.
berg944
New member
Thanks Paul,
the cheapest handling mod ever......air
My tubo had 30 psi all round when I bought it, so I kept them at this for a while.
The car wandered when it hit grids and tended to follow white lines, I thought it was the wide tyres or the front geometry.
The steering is know lighter and better. It drives where you point it (except in the wet when the rear end wants to overtake)
Mike
the cheapest handling mod ever......air
My tubo had 30 psi all round when I bought it, so I kept them at this for a while.
The car wandered when it hit grids and tended to follow white lines, I thought it was the wide tyres or the front geometry.
The steering is know lighter and better. It drives where you point it (except in the wet when the rear end wants to overtake)
Mike
chris_boyle33
New member
I don't claim to have any expert knowledge or owt, but mine is about 30-35ish front, and 35ish rear. it seems to be fine.
when i first got it i had them at about 40ish all round. it was a bit more interesting when wet, but pretty much okay.
I had a slow puncture on my passenger side rear, which i've now replaced. i damaged the tyre by driving it when it was down to 9psi. i didn't really notice much difference whilst driving it like this (until i got out the car and looked). You may by now be realising that i'm not the most fussy person on tyre pressures - so perhaps someone else could answer this better ! []
------------------
p.s. - does anyone know whose car this is which i've pinched as my jpeg? Its not mine, but its red and looks like mine. I really should have asked the guy if he minded before i pinched it - it was about a year ago now tho. Sorry!
when i first got it i had them at about 40ish all round. it was a bit more interesting when wet, but pretty much okay.
I had a slow puncture on my passenger side rear, which i've now replaced. i damaged the tyre by driving it when it was down to 9psi. i didn't really notice much difference whilst driving it like this (until i got out the car and looked). You may by now be realising that i'm not the most fussy person on tyre pressures - so perhaps someone else could answer this better ! [
]------------------
p.s. - does anyone know whose car this is which i've pinched as my jpeg? Its not mine, but its red and looks like mine. I really should have asked the guy if he minded before i pinched it - it was about a year ago now tho. Sorry!
Diver944
Active member
I do know that with the 16" wheels on later Turbos and S2s that (depending on the year) the book says either 36 all round or 36 front and 44 rear!!!!![] Most people find extreme wear in the centre of the tyre at these settings so do reduce to around the 34 mark.
Confused yet [8D]
] Most people find extreme wear in the centre of the tyre at these settings so do reduce to around the 34 mark.Confused yet [8D]
Diver944
Active member
<Anorak on>
We all know that too much air in a tyre will cause wear in the middle, and not enough air will cause wear on the shoulders.
One way to determine the optimum pressure for tyres ensuring that the full width of tread is making contact under your driving conditions is to draw a line of chalk, or Tippex, or masking tape across the width of the tyre. Then go out for a drive, stopping regularly and checking where the marks have worn off [8|] Adjust so that you get uniform wear but then keep an eye out over the next few 1000 miles.
<Anorak off>
Me, I just set mine to the factory 36 (for my car) then lowered a bit to 34 when I spotted slight wear in the middle
We all know that too much air in a tyre will cause wear in the middle, and not enough air will cause wear on the shoulders.
One way to determine the optimum pressure for tyres ensuring that the full width of tread is making contact under your driving conditions is to draw a line of chalk, or Tippex, or masking tape across the width of the tyre. Then go out for a drive, stopping regularly and checking where the marks have worn off [8|] Adjust so that you get uniform wear but then keep an eye out over the next few 1000 miles.
<Anorak off>
Me, I just set mine to the factory 36 (for my car) then lowered a bit to 34 when I spotted slight wear in the middle
pae
New member
This is related to a 924S, but if it helps I've got 7x15 with 215/60 Yokohamas. I tried them with 30/36psi f/r but the rear was too lively, particularly on bumpy corners. I am at 34psi on the rear which feels more compliant on bad road surfaces.
the idea about a tippex line across the tyre sounds neat - might give that a go and see what I learn. Anorak on, reporting for duty.
cheers ........ Phil
the idea about a tippex line across the tyre sounds neat - might give that a go and see what I learn. Anorak on, reporting for duty.
cheers ........ Phil
Diver944
Active member
We've had many long discussions as why the rear pressure is so high at 3 bar on the 1990 onwards cars. Consensus seems to be to avoid high speed blow outs when on extended Autobahn cruising at silly speeds. Previous to 1990 it was 2.5 bar all round (36psi)
I run my 17" wheels at 34 front 35 rear, this gives even wear across the tread. 44psi at the rear, wears out the middle in a few thousand miles and makes the car horribly loose at the rear
I run my 17" wheels at 34 front 35 rear, this gives even wear across the tread. 44psi at the rear, wears out the middle in a few thousand miles and makes the car horribly loose at the rear
Posts made and opinions expressed are those of the individual forum members
Use of the Forum is subject to the Terms and Conditions
