anonymousagain

Currently have 993 17" twist wheels 7" ET55, 235/45 front, 9" ET55, 275/40 rear.

Acquired a pair of 8.5x17 ET50 twists, so was thinking I could put these on the rear with 255/40, then swap the 9x17ET55 to the front with 245/40.

Figure the 9" will pull the 245's to nearly match the rear 255's on 8.5", but keep the offset to 55 in the front so they won't rub the inner fender on turning (ET50 definitely did...)

Any issue with running 9" front and 8.5" rear?

Thank you for any inputs.

Cosmo Kramer

I think a 245 with et 55 on the front will have the tire outside of the front fender. 235's are even borderline.

mark kibort

why cant you run the 9s in the back and the 8.5s in the front? are the offsets so bad that it wont work?

never mind. 8.5 is near 9 and 9"s need a 8" backspacing to work well. I dont think the 50ET would give you that. I seem to rememeber a test with a 996 front wheel that stuck the front tire well beyond the front fender side. not even close.

anonymousagain

hmmm... according to Andrew's nifty wheel fitment calculator for front:

9" 55ET with 245/40 will stick out 2.5mm beyond the fender.

Should I be worried about 2.5mm with stock height?

pcar928fan

Only if you hit a bad pot hole, go off roading, or don't like the Ghetto look of tires sticking out further than the fender of your car...

2.5mm will destroy your fender if you compress the suspension all the way for sure! Probably blow the tire too...

I wonder if you could have 5mm machined off the mounting face of the wheel w/o compromising strength?

hacker-pschorr

I've measured at least a dozen different Porsche wheels (OEM and aftermarket). All of them had just under 1/2" (12.7mm) of "meat" between the lug and the hub.

anonymousagain

thanks for the reality check Hacker, since I too wondered if machining off 5mm was an option.


so that settles it. I'll stick with the 7" ET55's and little 235's.

Thank you all for the inputs.