Lars911

Hi all!
Here's a problem that I have tried my best to ignore for the past 10 years: My Carrera -88 was originally delivered with 15" Fuchs rims, but since there was an option for 16" in the specs, I started a search for new rims. I soon found a set of beautiful 16" Fuchs that had once sat on a 944, but when put on my 911 I immediately saw that they would not work. That's how I learned about the ET (Einpress Tiefe, i.e. offset) specification. I returned the 944 rims and got my money back and finally located a set with what I though was the correct specification. (16"/7" ET 23.3 mm in front and 16"/8" ET 10,6 mm in rear as I recall, Porsche part numbers 911361020 44 and 911361020 45 respectively).

These worked well, but after wearing out the original set of tires and fitting Bridgestone Potenza S-03 my troubles began. Or at least I think that was when they began. I believe the tires are of the right size (205/55 ZR16 in front and 225/50 ZR16 in rear), but when I hit a compression in the road, the front tires will scuff against the fenders. It works well on the race track, so "normal" driving will not cause any harm, but apparently bumps in the road causes the suspension to compress more than does tight cornering. The way I drive this only happens perhaps once a year, but it removes some of the joy of driving.

I have tried to search for similar questions here on the forum, and have come up with several threads that indicated I should not have a problem (e.g. "16x7 on the front?"), but now when I check the drivers handbook for the car, it says the Carrera is specified in front to have either 195/65 tires on either 6J or 7J x 15 rims, or 205/55 tires on 6J x 16 rims, so it seems my 205/55 on 7J x 16 rims are out of spec, rim-wise but not tire-wise. There is no note of offset for any of these combinations in the Driver's Manual, but I would have expected it to be the same for all. I'm not quite sure where I initially got the 23.3 mm offset number, so if anyone could confirm or correct that I would be very grateful. As I said, I don't really understand why a 7J rim with the same offset as a 6J rim would cause a wider profile with the same 205/55 tire, but my guess would be that in my case the offset is wrong?

To be honest, I have posted this question on the 911uk forum earlier, but have not had much luck there other than a suggestion to check camber settings end ride height, but I don't think that can have much effect on my problem.

Cheers!
/Lars

NineMeister

Lars,
The 7" x 16" Fuch with 205/55 will fit, you just need to roll the front wheel arch as Porsche did with the 3.2 Carrera Clubsport. The Clubsport came with 8" rear and 225/50, however the 9" Turbo rear with a 245/45 will also fit. I run the 7" & 9" combination on my 3.2 without any issues, although I have also upgraded to Bilstein 160/161 & 220/180 shocks which help to control the compression.

NineMeister

PS
If the 944 16" Fuchs are still available I would buy them. The centres are completely different to the 911 version to provides additional caliper clearance for the 944 turbo - very useful to me so I could seriously upgrade the brakes. Why? I have a 320hp 993 engine in the back.....

Lars911

Sorry, the 944 Fuchs are a long time gone.
/Lars

Lars911

Thanks for the tip to roll in the arches, I will consider that in case I can't locate the correct 6Jx16 rim somewhere. I found a set here in Sweden on the major ad site, but they where polished and would not look right. I will keep looking.

I finally found a post on Pelican that listed all the different flavours of Fuchs rims here:
http://forums.pelicanparts.com/porsc...rs-offset.html
I also found a document from Porsche with a complete list of wheel specs for vintage models and it seems the front offset should NOT be 23.3 as I have thought, but rather 36! The 7Jx16 I have, with 23.3 mm offset are for the Turbo front or the Carrera rear. But if rolling the arches is as simple as it seems, that would make for an easier solution.

Cheers!
/Lars

The Brewmeister

Keep looking. 6J x 16 should't be too hard to find, many people don't like the flat face. I do like the flat face myself, it just looks right on the front.

Bill Verburg

I'd echo what Colin said, I used to run the 7ET23.3 & 9ET15 x16 Fuchs on my C3 w/ Bilstein hd shocks, but I shaved the front lips for more room. W/ Fuchs this was the best setup for my use until I put a 3.6 into the car.

Other things that can add clearance,
use a little more negative camber
all tires w/ nominal 205/55 x16 are not the same, there are different measured dimensions and shoulder profiles.
ride height- the lower the car the less lip room
try a shorter tire 205/50 x16 is ~.8" shorter than a 205/55 but has the same nominal width and tread

You want the widest wheel that fits the tire spec for best performance, 205/55 or 205/50 x16 are spec'd for 5.5 to 7.5" wheel, a 7 supports the tire sidewall much better than a 6 and will provide more ultimate grip.

similarly in back 245/45 x16 is spec'd for 7.5 to 9, for best performance the 9 is wanted. a 225/50 x16 is spec'd for 6 to 8, for that tire an 8 is best., The 245/45 tire has the advantage of being a bit shorter than 225/50 so provides slightly shorter gearing which can be nice at times.

David A

These are nicely made: http://braidusa.com/Wheels/Comp/BZ/BZ.htm

NineMeister

Using 7" & 9" x 16" Braid competition wheels on our latest build project. Very impressed with the quality and fit:

mrgreenjeans

they may be impressive to some, but not to all.

The correct 'look' is not present. Altho close, there is something about the rim lip width and definitely something about the shape of the windmill paddles or 'petals' as some refer to them. They appear too squared off where they meet the radius. And why do we always see them mounted up without center caps ?

NineMeister

No centre caps because the car is work in progress.....

And you are correct, the Braid rim has a slight lip whereas the original Fuchs are flat. In an ideal world we would have bought brand new Fuchs from Porsche but they are not available, hence you either risk buying a used set and pay a lot to refurbish them with the correct anodised finish or buy new equivalent in the finish you want for a lot less. As ever, decisions are always influenced by cost and availability.

JonSnow83

Colin- what tires are those? Pilots?

FWIW I'm running fuchs 7's and 8's in 205/55 and 225/50, but painted finish instead of anodized, with rolled lips and same bilstein set up Colin rec'd earlier. 8's will rub in front even with rolled lips I believe.

NineMeister

There you go, wheel centres:

NineMeister

Continental Sport Contact 2, N rated. Just fitted a set to my silver Carrera and I'm very pleased with them so far. Softened the ride compared to my old SO2's with more grip in wet & dry.

I believe you can fit a 944 Turbo 8" to the front with a rolled arch but not the 8" 911/930 version.

JonSnow83

Thanks Colin. Didn't realize those were available, just learned some pilot's in same size are as well. Those Conti's have a nicer look than the SO2's.

Not sure about the center caps though