Can I run 295/35/18's?
 

Anyone running 295/35's*instead of 295/30's? Any problems running these taller profile tires? Thank in advance. Sorry for such a noob question fella's. :cool:

I wouldn't recommend it. The taller profile tire in the rear of the car could cause problems with your PSM and/or the AWD system in your car.

Bummer deal... :(

Maybe some others have tried it and not had issues, but I believe the difference in diameter between front and rear might be great enough to cause issues.

What's your concern? Ride quality? Wheel damage?

NOPE! Way too tall. The rule of thumb is +/- 3% of OEM specs. OEM 18" rims run 265/35/18; diameter 25.30". Your current 295/30/18; diameter 24.96" is definitely within specs. A 35 section height will place you at diameter 26.12" or 3.24% over OEM specs. And, the latter would play havoc with the fore-mentioned as well as the ABS system. :cool:

I really like the Nitto Invo tires, the ride quality and road noise of those particular tires are awesome... but they only come in 295/35/18.

Thanks man, definitely not worth the possible problems.

Tires
 

I wouldn't chance it...After getting 2 rear tires same size my PSM system was wacked out for about a month..Ie. Coming off a freeway ramp the system would start breaking itself or felt like down shifting to compensate for what I was told was the difference in tread. Front old to rear new. Changed up the tire pressure and it corrected the problem. Scary though when you're flying around a ramp and your car decides to apply the brakes or down shift feeling..

I have already had this exact scenario happen to me with the current tires, so I know exactly what your talking about. I guess I'll just have to find a tire i like in the factory height.

The good news is that there are many good tire choices out there in a wide range of choices. I don't think you can go wrong with a set of Michelin PS2s, but they are expensive. I ran a set of Sumitomo HRT Z III tires on my car, and they were pretty darn good for the money.

it depends upon what is the diameter of your front tires. If it's the same then it's fine. Diameters can be found on tireracks site among others. One manufacturers tire with the same width and series will measure differently than another manufacturer

I disagree. Tire rack and porsche allow these cars to run 18 or 19 rims without problems. A 3% difference in 18 tires well inside this window.

Jb

what are you disagreeing with?

Tire Rack will allow you to configure a 19" package for the car that's pretty close to the diameter of the OE wheels. Lots of people run 19" wheels on the 996.

However, Porsche doesn't allow this. The largest wheel diameter recommended for the 996 by Porsche is 18".

With a C4 or C4S the critical factor is the differential between the front and rear tires. You can do this comparison with the specs on Tirerack. It might be possible to run the 295/35-18 with a larger size front tire, like a 235/40-18. I have the calculation on my computer some where, but not with me right now.