congaman

I've done a search but can't find the current thinking on this.

I've got 16" D90s on my C2 Targa. For the time being I'm keeping with these.

I've just changed all the tyres to N-rated Bridgestone S-02s. I asked the tyre fitters to set the pressures to 36 front and 42 rear (should be 44 but thought that high...)

The previous tyres were Pirellis (P7s front and PZeros rear) and looking at the last service invoice before I bought the car they noted the tyre pressures at 32 front and 36 rear.

Now, the point is that the ride now on the Bridgestones (and with those high pressures) is dreadful compared to what it was before. I'm feeling every rut and divett. What in your combined experiences are the best pressures front and rear? What can I safely take them down to without causing extra wear and reducing the handling feel?

With many thanks
Chris

Earlydays

I've run 32/36 on 16" wheels for years and like the balance....with no noticeable wear issues.

hepkat63

Just my two cents worth....

factory says 36, 44 (250, 300) for 16" wheels/tyres - why would you change that?

I would have thought that somebody with quite a few PHd letters after their names would have spent a lot of money, time and effort working out the best tyre pressures for that size wheel - track testing, braking, cornering, weight of the engine at the back etc.

Why compromise safety ? It's a Porsche, it's a sports car

congaman

Thanks for your comments.

I spoke to my local OPC yesterday. Apart from saying that my choice of Bridgestones wasn't the right one , the service manager said that different tyre makes have different characteristics and therefore different tyre pressure requirements.

He also said that 44psi is far too high for our roads here in the UK. So we agreed I should try 32psi front and 36 on the rear. Have done so and the ride is transformed. I need to work out whether I've gone down too low for spirited driving, but certainly for London roads I'm not now getting shaken about!

As a Porsche newbie, I've realised now that before buying anything (starting at tyres) I should seek advice either on here or from a decent service specialist.

There's always a moral to a story

tdiquattro

Bridgestone S02s are superb tyres, and suit the 964 in 16" form perfectly, your OPC staffer is talking crap.

I have been trying various pressures and am on 36/38 at the mo, just have a play and see how you get on.

hepkat63

Oh, and one other thing to note would be Insurance Companies. I hope you will never need your insurance company, but if you were involved in an accident and they found you were not running the factory tire pressures, it could be a 'get out' for them.
I'm not saying that they would - but i have a love/hate with insurance companies and have read plenty of 'gotcha' stories in-so-far as then refusing to pay claims when owners have swapped out or not adhered to anything stock without telling them first.

Harry Apps

+1

The "B" SO2s are listed as approved by Porsche in their 2013 list of approved tyres; however, they only list the N3 spec. That said, don't you just love it when an OPC knows better than the experts.

congaman

Mine are the S02s, N3 rated.

Regarding the OPC, I think it was just his own opinion, but happy so far with the Bridgestones, although they do have a bit more road noise (even though they were rated quieter). My other observation is that there is more of a judder at speed through the steering wheel. I'll get them re-balanced by another tyre fitter.

tdiquattro - I'll try 36/38 sometime to see what different that makes.

Thanks all for your help.

jevvy964

IIRC 44 is the max cold PSI for an SO2, no need to be anywhere near that IMO. Get a 44psi tyre hot and it'll be close to 50, might as well run solid rubber tyres at that pressure!

Ive driven quite a few 964's on many different tyre/wheel size combos and think I had the most fun on D90 16's and that was with 8's on the back with 225's on. I'd love to try one with 9x16 with D90's with 245/45 on the back but need to find a pair first!