New Porsche Owner - Tire Size Q

[Dejathoris]

First of all, I love this site. Lots of great info like NSX Prime I use for my NSX. I just bought a '72 911 three days ago, lowered with 930 Turbo flares, "S" cam, turbo tie rods, etc. Car has 15x8.5" (aftermarket) Fuchs at all corners, with 215/55 in front and 245/50 in rear. I need to replace the front (Kumho Ecsta) tires because they were made in 2002 (even though tread is fine). Rear tires are couple years old Dunlop Sport 8000. In reading the Tire Bible, seems that 215/55 size is better suited for 6"-7.5" wheel, not the 8.5" I have. So the tire is probably stretched some though it fills the wheel wells fine. Am I better of getting 7.5" wheels for the front, and matching the Dunlops? Most people state to get all 4 matching tires, though I have different front and rear tires on the NSX with no issues (both tires have similar performance characteristics). Any informed input is appreciated.

[Dejathoris]

Although I did not receive a reply , I decided to keep the wheels and buy tire size 225VR60/15. A little wider than before, but will fit the turbo wheel wells just fine.

Please close this thread.

Thank you.

[Bill Verburg]

Originally Posted by Dejathoris

First of all, I love this site. Lots of great info like NSX Prime I use for my NSX. I just bought a '72 911 three days ago, lowered with 930 Turbo flares, "S" cam, turbo tie rods, etc. Car has 15x8.5" (aftermarket) Fuchs at all corners, with 215/55 in front and 245/50 in rear. I need to replace the front (Kumho Ecsta) tires because they were made in 2002 (even though tread is fine). Rear tires are couple years old Dunlop Sport 8000. In reading the Tire Bible, seems that 215/55 size is better suited for 6"-7.5" wheel, not the 8.5" I have. So the tire is probably stretched some though it fills the wheel wells fine. Am I better of getting 7.5" wheels for the front, and matching the Dunlops? Most people state to get all 4 matching tires, though I have different front and rear tires on the NSX with no issues (both tires have similar performance characteristics). Any informed input is appreciated.

Usually on a 911 you use different size wheels & tires f/r.

typically w/ 930 fenders 8 & 9Fuchs 225/50 & 245/45 x16 are used though of course you can go wider especially if you get rid of spacers and use wheels w/ appropriate o/s

for example a desirable fitment using 930 fender f/r and 911 hubs f/r is
9ET15 & 11 ET-8 w/ 255/40 & 315/35 x17

there are of course lots of other variations in use too.