Edward

I've got a narrow/bodied coupe and am looking into a set of 17" from a 996 with Kumho 700s. While the fronts are same offset as my Cups, the rears' offset is 70mm.

Questions:

- Are spacers absolutely necessary? Can I get
away without them?
- If absolutely necessary, what size spacers(assuming 15mm?) and will the stock studs work?
- The rear Kumhos are 275/40s. Isn't this a bit large for a 9" rim and will I experience any rubbing on stock "school bus" (for E.J. ) suspension.

Looking forward to advice/assurances here! Thanks

Edward

Viken

If those are 17" wheels off of a 996, the rear wheel should have a 55 mm offset. All 17" wheel variants as of the "Carrera" (996) wheel design have had a 55 mm offset. The only 9" x 17" wheel I know of with a 70 mm offset was a "Cup Design '93" wheel used on some early 993's. I believe this wheel will work on a narrow body 993 but a 10-15 mm spacer improve the looks a bit.

Edward

Viken,

The owner of the wheels says they're 17 inchers off his '00 C4 Coupe. He says they're 70mm offset...could he be mistaken? I know my Cups have the offset marked on the rim itself. Do all OEM rims follow suit?

You also mentioned 10-15mm spacers would improve the look. Are my studs long enough to accomodate?

Also, what do you think about the 275 Kumhos on a 9" rim? This seems a bit wide for a 9", but maybe "R" compound measures differently? Thanks!!!

Edward

STLPCA

[quote]Originally posted by Edward:
<strong>The rear Kumhos are 275/40s. Isn't this a bit large for a 9" rim and will I experience any rubbing ...</strong><hr></blockquote>

Edward
9" is an approved (although minimum) wheel width for Kuhmo. I don't know if you'll experience rubbing. If it helps, some generic comparisons between the oem 255/40x17 ET55 & 275/40x17 ET70 (the 15mm offset difference equals .59"):

..................255/40........275/40
Diameter:........25.03"......25.66"
Tread Width:....10.04"......10.83"
Sidewall Height..4.02".......4.33"

Extra Clearance Needed:
Tire Outside:.....-.20"
Tire Inside:.......+.98"
Wheel Outside:......-.59"
Wheel Inside:.......+.59"

Viken

[quote]Originally posted by Edward:
<strong>The owner of the wheels says they're 17 inchers off his '00 C4 Coupe. He says they're 70mm offset...could he be mistaken? I know my Cups have the offset marked on the rim itself. Do all OEM rims follow suit?</strong><hr></blockquote>

Yes, some wheels have the offset inscribed right next to the valve stem and so did the 996's 17" Carrera wheel. However, if his rear wheels have a 70 mm offset, they are not factory installed Carrera wheels. All 17" factory rear 996 wheels had a 55 mm offset.

[quote]<strong>You also mentioned 10-15mm spacers would improve the look. Are my studs long enough to accomodate?</strong><hr></blockquote>

Probably not but if you got Porsche or H&R spacers, they would come with the proper studs. Personally, I would never buy wheels requiring spacers unless it was my only choice.

[quote]<strong>Also, what do you think about the 275 Kumhos on a 9" rim? This seems a bit wide for a 9", but maybe "R" compound measures differently?</strong><hr></blockquote>

The 275 is a tight squeeze on a 9" and will most likely rub against the fender (with a 55 mm offset) or the suspension (with a 70 mm offset). I would stick with a 255 tire on the 9" wheel.

MikeG

Hi Guys,

I'm the one with the wheels. The wheels have a 55mm offset. I must have mis-conveyed that what the 993 needs is a 70mm offset. Sorry for the confusion.

BTW, the tires did not rub on the 996, I have no idea how it would do on the 993. 275 is about the limit on a 9" rim, but the tire is not bulging at all, actually, it looks quite beefy and nice


Mike

Edward

All,

Thanks for the input...I can always rely on this board's congeniality and knowledge! <img src="graemlins/xyxwave.gif" border="0" alt="[bigbye]" />


Mike, thanks for the clarification. Perhaps it was I that misunderstood. Did you get my e-mail? Let's talk

Edward

E. J. - 993 Alumni

Edward, my school bus runs the 275s Hoosiers at the track on the stock 9" wheels with no problems with rubbing. Works great.

E. J.

Viken

[quote]Originally posted by E. J.:
<strong>Edward, my school bus runs the 275s Hoosiers at the track on the stock 9" wheels with no problems with rubbing. Works great.</strong><hr></blockquote>

E.J.

From what I remember, your car is not lowered. I'm not sure if Edward's is or isn't but that would make a difference.

Edward

Viken,

Thanks, as always, for the input. Mine is not lowered.

E.J.,

Thanks for the chiming in as well! BTW, if yours is the schoolbus, does that make my '95 GuardsRed a firetruck


Edward