orangecurry

There are three versions of the 8J Cup design 93 wheel, or Cup 2 if you prefer.

ET52 which can be for the front (or for the rear of the 964), ET70 which is for the rear to allow snow-chains, and an ET30

As I understand it, the 2S had 'normal' 9J ET55s on the rear, with a 25mm spacer from the factory.

Is the ET30 8J wheel the factory winter rear for the widebodied cars, or is it actually for another Porsche?

Thanks!

Railmaster.

All factory 993 front wheels are ET 50, 52 or 55.
All factory 993 rear wheels are ET 30,40,55,65 or 70.

The ET 30 8Jx17 is specified as a winter wheel for 993 Turbo and 4S.

So yes!

P-daddy

The C2S had the 9J with factory 31mm spacers on the rear, not 25.

orangecurry

Thanks both - my bad on the spacers. I was just going on memory/maths, rather than looking it up.

orangecurry

doh! It was in TSB 4440 in front of my eyes!

NB It seems that the 8J 52 wheel was probably only envisaged as a rear wheel, even though it does fit the front.

Approved Winter Tires, Wheel Sizes and Spacer Ring Sizes Tire Sizes Wheels Offset (mm) Axle Notes
205/50 R 17 89 H M+S 7J X 17 55.0 front 5mm spacer ring allowed per wheel, part number 993 361 605 00. *
225/45 R 17 90 H M+S 8J X 17 30.0 rear Can use tire chains, part number, 996 361 920 00

205/50 R 17 89 H M+S 7J X 17 55.0 front 5mm spacer ring allowed per wheel, part number 993 361 605 00. *
225/45 R 17 90 H M+S 8J X 17 30.0 rear 17mm or 21mm spacer ring per wheel allowed, part number 993 361 617 00 * & 993 361 621 00 * respectively. Tire chains cannot be used.

205/50 R 17 89 H M+S 7J X 17 55.0 front 5mm spacer ring allowed per wheel, part number 993 361 605 00. *
225/45 R 17 90 H M+S 8J X 17 52.0 rear 17mm or 21mm spacer ring per wheel allowed, part number 993 361 617 00 * & 993 361 621 00 * respectively. Can use tire chains, part number, 996 361 920 00

205/50 R 17 89 H M+S 7J X 17 55.0 front 5mm spacer ring allowed per wheel, part number 993 361 605 00. *
225/45 R 17 90 H M+S 8J X 17 52.0 rear 25mm or 31mm spacer ring per wheel allowed, part number 993 361 625 00 * & 993 361 631 00 * respectively. Tire chains cannot be used.

GregSC

Not to unduly highjack the thread, but I have a question concerning the 8J ET30 wheels under discussion. I was able to pick up a set of cup2 wheels last summer. The fronts were ET55, but the rears are the aforementioned 8J ET30s. I realize these were originally designed as winter wheels for the 993TTs, but will these fit a narrow body 993? ('96 Coupe to be exact) Thanks in advance for any insight you can give.

orangecurry

If you already have the wheels, test fit them, though unless they have tyres that's not gong to give you a definitive answer..

But I think the maths says they will be 22mm further 'out' from the hub than the ET52 8J rear that is 'correct' for a NB car, so you may get away with it.... also depends on what tyre you are going to fit.

Good luck

GregSC

Thanks for the reply! Unfortunately they're tireless so I can't test fit them at the moment. I know the typical cup2 rear wheels are 9s, and these are 8s, so if I am thinking correctly add 25mm (et55-et30), take away an inch and I should be good, was just hoping someone had some experience running these on a narrow body. Also, I don't know if there would be any disadvantage running these instead of the typical 9s.

orangecurry

I'm not sure you can subtract the inch - I'll probably get this wrong but I think the offset number is the distance from the hub-mating surface of the wheel to the centre-line of the wheel, not the inner or outer rim.... therefore you can only subtract half an inch?

Offset messes with my head.

And what tire are you thinking of using?

225/45/17 is ideal on an 8J

Allegedly a 255/40/17 should only be mounted on an 8.5J to 10J rim, not an 8J

GregSC

I would say you're correct about the offset. My knowledge of the calculus involved is very limited for sure. I hadn't considered a tire size yet, wanted to figure out for sure if the rears would fit first, then decide whether to have them refinished or not. They're not in the best of shape.

TJ993

Bump Delete - Answer above TT 993 winter wheel
Has anyone tried to install on the front of a 993?
Thinking Spacers or better with longer studs?
now if u need these rims send me a pm