I am putting Turbo II Factory 19" wheels and tires from a 997 on my 2002 996 C4S.

Front is 235/35/19 ( 25.5 inches high)and rear is 305/30/19 (26.2 inches high) ..am I ok on the 2.7% % difference ( 26.2 divided by 25.5) of front and rear for my all wheel drive ?

Thanks

Also posted in Tire forum

 

Yes. Lots of turbo guys run that combo for year and years no issue. I run that combo now. The closer to the OEM size ratio the better but you won't run into any issues. When it comes time to replace tires go with a 245/35 front, it will drop the ratio to about 1% if that's something you're worried about. Better to be closer but don't lose any sleep over it.

My car is lowered 1.1" on H&Rs, had to roll the rear fenders slightly to accommodate the 305/30, no issue on the fronts at all.

 

you need to use 225/35/19 and 305/30/19 Combo.

 

Thanks !!!

 

Hi Zookie, sorry but that information is incorrect. Can you explain how going to a 225 & 305 combo which has almost a 4% differential (vs. the 2.8% in the 997 setup) is the correct combo?

OP, the 997 runs 235/35-19 & 305/30-19 which is a 2.85% variance to the 996 tire sizes. This sizing will work as I have already said. If you change tires you need to go WIDER (not narrow as Zookie has stated) to a 245/35 front with the 305/30 rear. This is a VERY WELL documented combination for the AWD cars. This bring the differential between F&R down to 1.75% vs the 996 sizing.

Either the 235 or 245 front will work with the 305 rear but NEVER a 225.

 

mmmmm you are right... I wonder what I compared before. never mind what I said