hey guys,

i recently just purchased some wheels for my car and since its AWD i would like to know some of the tires sizes people are running so i dont mess up my differentials. I would also like to run some pretty aggressive tires like RT615's DZ101 star specs, any type of R-comp really.

the wheel specs are 19X8.5 and 19X11

any help is much appreciated,


thanks
siam

 

19" wheels/tires aren't recommended by Porsche for the C4S, so it's hard to say what might happen to your differentials.

 

Given OEM is Front: 225/40R18; Rear: 295/30R18. And, OEM wheel diameter is: 25.08 F; 24.96 R. I would go with: F 245/30R19 (24.78 diameter; - 1.2%); R 305/25R19 (25.00 diameter;+ 0.16%). Good luck.

 

i run 225 35 19 8.5 wide front and 315 25 19 12 wide rear. Front and rear tires are 25.2 diameter

 

you run this on your C4S??

 

yes, as long as the front and rear tire diameters are the same or very close you shouldn't have a problem.

 

awesome! thanks a lot for the help, what tires if i may ask

 

wtf? thats the stupidest thing i have ever heard...

OP 19's you need to Run Front 225/35/19 and Rear 315/25/19... You can also use 235/35/19 in the Front

yes and have been for 5 years... 100,000km plus

 

Siam, you can run 235-35-19/315-25-19, but the tire choice are narrow and don't think you can get any aggressive tires with that. Another choice is 295-30-19 rear. I have them on my TT for some times now and they actually feels better than my last 315 setup due to more side wall. Both are within Porsche recommend 4% front and rear diameter ratio. Sent me some high-res. pics once they're on!

 

I'm running Toyo T1R

 

I'm running the 235-35-19/315-25-19 set up lowered on PPS10, dog bones, adj toe r toe steer and drop links. No issues. Just be careful with the offset. R compounds are limited in these sizes.

 

thanks ray!!

yea i just ordered my JRZ coils today so i am just waiting on some tires now but i know for sure i would like to get some R-comps. ill look into what companies make the sizes you guys have all suggested and see what i can do with my budget haha.

thanks again guys!

 

What's stupid about making a decision based on test data?

Many people who I consider to be quite knowledgable about Porsches and 996s in particular recommend staying at 18-inch wheel sizes for this vehicle, just like Porsche recommends. I don't think they are stupid.

That being said, you can put whatever you want on your own car. I've seen 996s with 20-inch wheels before. There's probably someone who has put 21s on or is considering it.

My point is that asking for a recommendation on a tire size when you're using a wheel size that's not recommended by the manufacturer will give you answers that are not based on any pertinent data. You'll get answers from people who say things like: "use this size, it doesn't rub at all" or "I'm using this and it doesn't cause any problems". If that's how you'd like to make a decision on tire size, then go for it. If you'd like to make a decision based on legitimate testing by the manufacturer, then stick with the Porsche recommended sizes.

 

I could not agree with you more with both being of equal diameter. Though aesthetically speaking, I feel a 225 35 19 will not fill the width of an 8.5 rim. It may leave a 1/2" gap between the bead of the tire and the bead of the rim.
Thus, a 245 30 19 would address this issue with a slight difference in diameter. Personal choice, I presume.

 

"wtf? thats the stupidest thing i have ever heard..."

Zookie!! LOL you beat me to that comment! I was going to say the EXACT same thing.