loot87

My 91 C2 965 came with one odd rim on the rear left. Neither the PO nor the shop that did the PPI noticed it. 3 wheels are 18" 993 Turbo Twist style like the wheel on the left. The other is 18" 996 Turbo Twist style.
I'd like to buy another 993 to match the other 3. The Mille Miglia Cup3 and Wheel Enhancement Porsche Technology both look similar. I have no idea whether it's hollow or solid spoke.



The only distinctive marking on the 993 style is this:



The 996 rim has this same logo on the inside.

The inside of the 993 wheel looks like this:



There are only number strings and "Made in Italy". UPDATE: It also has "ET47" as one of the markigs.

I suppose there is probably something under the tire, but I really don't want to remove it just to ID the wheel.

Thanks for any help IDing this wheel. I just want to pick up something that looks and drives the same as the other 3.

Chris

Computamedic

Chris,

The logo you mention is the Mille Miglia logo. Any "real" Porsche wheels will have a part number (e.g. 993.xxx.xxx.xx cast into the back side of the wheel - not under the tyre). The Mille Miglia wheel should have the size and offset cast into the rear side of the wheel in the centre section.

Hope that helps.

BTW - What, pray, is a C2 Turbo??? There never was any other sort of Turbo with the 964 series!! Unless, of course, you mean a C2 with an aftermarket turbo - silly me!!!

Regards

Dave

PS. As you probably now realise, you'll get a much more prompt answer if you post in the 964 forum - few look here.

loot87

No, it's just a 965. I saw other people call it a C2 Turbo, but you're right, that is redundant since there wasn't a 964 C4 Turbo.

Thanks for the heads up. If they're all MMs, then I'll just get another off of Tire Rack. It does have the size and offset cast in (18x10 and ET47).

I know, the 964 forum rocks... I just wanted to post in the right place.

Computamedic

Chris,

To the best of my knowledge, the MM 18x10 ET47 wheel was designed for fitment to the rear of a narrow bodied car. I think the wheel offsets for the wide bodied cars are different so it may be worth doing a bit of checking before you get carried away. I have the same wheel on my car but it's a wide body conversion so it has the narrow body suspension. The trailing arms are different on the factory wide bodied cars.

Regards

Dave

PS. Chris, I actually checked in Adrian's book and it looks like the offsets are OK. The standard Turbo rear wheels were ET55 so the ET47 wheels will be a little further out - and the extra 1" width will make a little more difference too.

loot87

The stock 18x10 Turbo Twists use a 40mm offset, right? So wouldn't a wheel with 47mm offset on a stock trailing arm protrude farther? My other rear uses 47 and looks OK (wheel doesn't stick out from fender, but is pretty much flush).

Computamedic

Chris,

The Porsche wheels use a negative offset - so the greater the offset the greater the mounting flange moves to the OUTSIDE of the wheel - hence you can use a 10mm spacer to make an ET65 wheel into an ET55 wheel. So your example is not right.

As long as the ET47 wheel fits right and doesn't touch anthing on the fender or inside wheel arch (or oil pipe) then you are fine.

Regards

Dave

loot87

So the stock 40mm wheels actually protrude 7mm farther than the 47s? That's surprising since these 47s are pretty much flush now. If I had 40s, it seems like the tire would stick out of the wheel well.

Computamedic

Chris,

Probably not, since any ET40 wheel would almost certainly NOT be 10J. The standard Turbo wheel was only a 9J - so 25.4mm narrower. That would give 12.7mm less on each side of the wheel - so 7mm less offset would still put the older wheel inside the new one.

There is a useful calculator here

Regards

Dave

cobalt

Jumping in late but maybe I can help.

To begin with the term C2 turbo was used when Porsche switched over to the 964 turbo body style. This was used by many to differntiate between the older 930 turbos and the newer turbo model. The term 965 is also an incorrect term used by many. It was a designation assigned by Porsche for a model based from the 959 that never came to be. Both terms are now widely used and accepted by most owners of these cars. In fact there is a website called www.C2turbo.com .

Regarding wheels and offsets. Since your car is either a 91-92 964 turbo, stock sizes were 17" in 7" and 9" widths. You are using 18" wheels which were not approved by Porsche until the '94 964 turbo 3.6. Special 3 piece "Speedline for Porsche" wheels were fitted. The rear size was in fact a 10 inch wide wheel with an offset of 61mm while 8" wheels were fitted in the front. The 40 mm offset you are using was designed for the narrow body 993's. Since they are not factory I would say what you have are solid spoke. I have a set of factory 993 hollow spoke with an offset of 40mm that I use for autocross tires. They limit the size of the tire you can use in the rear. The most I can fit comforatbly with my car lowered is the stock 265 35 size tire. While on my factory wheels with an offset of 61mm I can fit a 295 30.

I hope this helps.

cobalt

BTW come over to the 964 turbo board with these questions. Everyone there is willing to help with any questions or concerns.

loot87

Cobalt,
Thanks. I'm on the turbo board and have posted there about other things. There's just more conversation over here. I definately don't have the 3 piece speedlines as my offset is 47. The offset and weight of the MMs match. I ordered one from TireRack, so we'll see next week.
Thanks.
Chris