bship

I would like to move my fuch 16inch 7's from the back to the front and buy some 8's or preferably 9's for the back. My 83 SC is stock and has not been lowered will the 7-9 combo fit without any modifications?

Bill Gregory

Scott,

You may want to read the 911SC FAQ, as wheel fittings are discussed, and it might answer other questions. You can move your 7's to the front and use either 911 8" or 944 8" or 9" Fuchs in the rear, no problem. If you go with 9x16 Fuchs, people usually go with 245/45x16 tires. Depending how you use your 911SC, 245's in the back with 205's in the front may contribute to increased understeer. If you plan to keep 225's on the 7's, you should check for fitment.

Bill Verburg

The 205/55x16 on 7" and 245/45x16 on 9" combination works really nicely. The additional understeer is only noticeable at 10/10ths on a track. It is less apparant than the understeer induced by a ZF. If it is a problem(not likely) tune it out w/ a stiffer rear sway bar(you always wanted adjustable bars anyway, didn't you).

There have been some reports of the front 7x16 205/55 (particularly on the drivers side) interfering w/ the lips. Most (including me) have not had that issue. If there is interference then roll or shave the lips to alleviate.

I would caution about the use of the 944 8s in the back, they have a +23.3 mm o/s(as do the current stock 7s) but the additional width on the inboard side can necessitate the use of spacers(never tried that one myself), just a heads up about a potential problem). The correct o/s for the rear 8s is +10.6 mm.

The +15 mm o/s 9s fit perfectly w/ 245/45x16 tires, giving slighly better gearing than the stock 225/50x16

I experimented w/ numerous permutations of 7,8,9 x 15,16 front 205/50x15,205/55x16,225/50x16 rear 225/50x15,225/50x16,245/45x16. The best all around trouble free was the 7&9 205/55 & 245/45 x16

Bill Gregory

[quote]<strong>I would caution about the use of the 944 8s in the back, they have a +23.3 mm o/s(as do the current stock 7s) but the additional width on the inboard side can necessitate the use of spacers(never tried that one myself)</strong><hr></blockquote>

I ran both 8's on the rear of my SC - 911 8x16's, which I traded for 944 8x16's, and both fit and ran fine, without any spacers.

Bill Verburg

Bill, the lip of a 944 8 sits 12.7 mm further inboard from the lip of a 911 8. If there was no interference, which I can easily believe, didn't it at least look odd?

As I said I never used that wheel in the back, I do vaguely remember hearing grumbles about their fit. For the life of me I can't remember if it was interference inboard or appearance. <img src="confused.gif" border="0">

Bill Gregory

Bill,

Only used it on the track with 225's - I don't recall it looking out of place, and nobody ever made any comments about it. I liked them better when I moved them up front and added 9's to the back, however.

Bill Verburg

Agreed 944 8" front w/225/50 and 930 9" rears w/ 245/45 is the best short of 17s <img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />

bship

Thanks for the feedback. If I am going to buy new fuch's should I go ahead and put 17's all the way around. How wide can I go upfront and in the rear?
8's upfront 9's in the rear?

Bill Verburg

On my Carrera I am using 235/45 & 275/40 on 8" & 9.5" 17s. I do not reccommed this unless you are really serious and will do fairly extensive work to all 4 lips, oil lines and trailing arm bolts.

I have also seen 245/40 & 275/40 on 8 & 10" 17s. These will entail even more work.

For fairly trouble free installation 8" & 9" 17s using 225/50 & 255/40 is probably best.

Keep in mind that each wheel manufacturer uses slightly different o/s and each tire manufacturers nominal and measured sizes may be very different, some run large and some run small. For a trouble free install do your h/w thouroughly.