MMP1

Hi,
Will the following Cup I wheels (and tires currently mounted on them) fit my 1980 928S (euro model) without any modification?
FRONT WHEELS:
7 1/2 X 17 WHEEL SIZE - OFFSET=E15
225X45 ZR17 TIRE'S

REAR WHEELS:
9 X 17 WHEEL SIZE - OFFSET=E23
255X40 ZR17 TIRE'S

If not what is needed to make them fit. Any thoughts on the effect it would have on ride feel, speedometer reading or any issues I would should be aware of?
I currently have the original 16" dish wheels on the car and would like to upgrade to 17"
Thanks!

Rob Edwards

The front wheels will stick out 50mm further out than the typical 7.5" 928 front wheel, or 2 inches. So the wheel will be an inch outside the front fender. Only way to make that work will be to jack your ride height up above 200 mm. I'm afraid those wheels won't work on a 928.

Hold On

Short answer, NO

MMP1

Bummer. But thanks for letting me know before I get over excited and purchase them. Really want to move up to 17" wheels for a more filled out finder look without effecting the ride!

Weissach

I've got a set of original 928 GTS Cup 2's for $700 + shipping. PM and I'll send you the details

hlee96

that’s a great deal. Congrats!

By the way, the lowest offsets that’s acceptable for cup I is 55 front and 47 rears (common 911 offsets) for 928 (I have them on my ‘79 auto).

FredR

You can fill out the wheel well with incorrect offsets that does have an impact on the handling as you lose NSR [negative scrub radius] or you can have the correct offset for the suspension design if you have the right wheels such as those offered above. The only way you can have both is if you fit wheels like mine with 9.5 inch rims and ET68 carrying either 255 or 265 rubber. To be fair most folks do not push the envelope so losing NSR does not seem to worry most.

Personally I find it pointless fitting something that detracts from the Porsche design considerations but each to his own as it were.

MMP1

Was gone for the Thanksgiving weekend. Just wanted to thank everyone for all their advice. Appreciate it all very much.

BrianG

I like the look though.

Wisconsin Joe

You wouldn't like the look with offsets of 15 front and 23 rear. The wheels would stick waaaay out.