porsshe wheels 17x8.5 rear for sb 74

[flat]

I don't think the 8.5's will fit stock fenders. I have 8et70s on my 1302 rear with 986S brakes and it 'just' fits. I had to trim the body mount in the fender a touch so that the tire (225/45) doesn't rub on compression. With 8.5 the offset is typically 52 or 55mm, so you'll be out too far with Porsche brakes. With stock drums or the regular rear disk kits (most are +8mm per side over stock drums) I think you'll be just on the edge of the fender with a conservative tire choice.

Lanner