245/40 rubber on 8.5 wide wheels

[200kclub]

What does the community think about this tire setup? In theory they fit fine but people seem to only put 245's on 9 inch wide wheels for looks.

Is this only for looks? Does the extra sidewall over the side of the rim (about a quarter inch each side for 8.5") negatively affect performance.

I'm currently running this rubber on 8 inches square. Michelin's size chart says this is okay, but I just believe that it makes the car feel less responsive on turn in.

Pic related.... balloon tire

http://i.imgur.com/Up7hs.jpg

[ErikB34]

245's on an 8.5" wheel is really common, even for OEM's. BMW, Infiniti, etc.

[Blackateer]

its understandable for it to feel less responsive because of the amount of rubber. With more rubber means more flex. The flex is what makes it feel sluggish but obviously with extra rubber at the right tire pressure mean a greater contact patch.

[200kclub]

245's on an 8.5" wheel is really common, even for OEM's. BMW, Infiniti, etc.

Ive heard that. I think porche runs them in oem fitment.



its understandable for it to feel less responsive because of the amount of rubber. With more rubber means more flex. The flex is what makes it feel sluggish but obviously with extra rubber at the right tire pressure mean a greater contact patch.

Im only running 40mm sidewall though. However, the added rubber on the side does give it more flex which is why I need a bigger wheel.

[Ianik]

Im only running 40mm sidewall though. However, the added rubber on the side does give it more flex which is why I need a bigger wheel.

You don't run 40mm sidewalls but sidewalls which heights are 40% the width of the tyre...

245/40/17 means about 245x40/100= 9.8cm > 98mm

[200kclub]

You don't run 40mm sidewalls but sidewalls which heights are 40% the width of the tyre...

245/40/17 means about 245x40/100= 9.8cm > 98mm


Thanks for the clarification. My knowledge of the metric system is severely lacking to have thought that.

[yip]

Not all 245/40's are going to look or fit the same.

My 245/40 PS2's would probably look better on a 8.5 than my 9's. I don't quite understand it but they look a little stretched on my 9's.

[jeremy5000]

I run 245s on 8.5" wheels... Next time around I will probably go 255 fwiw.

[dsm1983]

my MBZ c350's stock rear tyre size is 255/40/17 and that's on an 8.5" wheel. doesn't seem overly meaty.

[lithium726]

That's the stock size for the rear of the M3. It's fine.