Porsche Enthusiasts Club Forum

I recently bought my 2003 996 C4S. On purchase, the car was fitted with 'N' rated tyres all around, Michelin Pilot Sports on the rear and Pirelli P Zero's on the front. All had over 7mm of tread left. The car has had a strong tendency to 'tram line' on all types of road and all types of surface. I wouldn't describe it as frightening, but it certainly made me keep a tight grip on the wheel. I had always suspected that the different Brands of tyre (and compounds) were probably the cause of the problem. This view was reinforced by the advice i had received from other members in our region.
Today i went to A2 tyres in Sittingbourne, Kent, where the RO's had taken us on a visit back in August 2016. The team there bent over backwards for me. I opted to replace the P Zero's on the front with Pilot Sports so that the car now has Michelin's all around. This was the cheapest option for me on the day. I also had a full Geo check done and some correction carried out. The difference in the handling now compared to how it was earlier today is incredible. Quieter, less twitchy, and more relaxing. What percentage is due to the Geo setup or tyres could be debated, but in my opinion the tyre change has had a the greatest effect. I'm sure that had i taken the option to replace the rears with P Zero's (more expensive for me) the effect would have been similar. Conti's all around would have been my preferred choice, but prohibitive on cost.
I had read on another forum of a guy experiencing similar issues to those i was having with my car, so i hope that this thread helps others if they are in the same boat.

Stuart

Glad you have sorted it out.

You should enjoy pushing the 4S through the twisty stuff, the grip when it is set up properly is awesome. I destroy a set of rears every 7000 miles in mine, love it.

The various PZeros do seem to tramline, I had them on the Boxster & one of the Jags. Given a Conti or Michelin choice I would go Michelin every time, they were awesome on the Boxster.

Nothing wrong with the Michelin other than they are often on back order for the 295, so i use Conti.

niche application so presumably made in batches.

In some cases the Michelins work out cheaper than a few tyres in the long run.

On my M3 the rear Falken FK453s covered 8,000 miles before they were on the limit. The PS2s on the 944 Turbo with 300BHP came with the car. I covered 10,000 miles in it and sold the car with them on it.

On my 991, Michelin Pilot Super Sports (non -N rated) gave me 27000 miles on the rear and I reckon I'll get 35000+ on the front set

Thats amazing, i got 7000 miles out of a set of Pilot Sports

Glad the guys at A2 did you proud.
I'm a fan of Conti's, I'm just on 8K with mine and the rears are still like brand new, not sure if that's down to a good set up or driving like Miss a Daisy, will let you decide

I've just fitted a set of Pilot Supersports to the 997. Jeez, they're noisy.

Back on track while I know it's not a Porsche it's just to remember that the problem could be bushes in some cases.

On my E46 M3 it was always a little nervous over the white lines, even the previous owner mentioned this. I always thought this was down to the front tyres. They had worn very badly due to poor geometry at some point in its life which was then corrected when the damage was done. It had Falken FK452s on the front that had worn strangely and FK453s on the rear which had worn well to be fair.

When it went in for the airbag recall BMW kindly told me that my tyres were pretty close to being changed. While I knew this it is painful when you know that even a mid range tyre is around £150 a corner.

In order I did this:
-Changed the rears to PS4s ; it was quieter, smoother and grip alot better on the back to the extent the front actually began to understeer in a few cases. But there was no difference.
-BMW E46s are known for subframe mounts cracking. I had these reinforced and had Poly subframe bushes fitted courtesy of SuperPro/Flex.
WOW - it felt different even leaving the shop. The motorway trip down to the shop was twitchy! The journey back was far from it. It literally glid down the road irrespective of the white lines. Sure the front end now really didn't feel that connected but the car for the first time ever felt spot on. I will admit the poly bushes do transfer sligthly more noise in some parts but overall it's a huge improvement ; alot of E46s I've driven since feel 'loose' on the rear.
-Going to MPS4Ss up front just improved things that little more ; the front end now has regained its front end bite with it feeling the nicest it ever has.

What's the moral of the story? It's not always the tyres . But tyres can wear to bad or moving geometry which can also cause issues.