16x7's on the rear on a narrow body car?

[Britain Smith]

I have seen several post about people putting 15x7's on the rear on their narrow body cars, but I want to know if 16x7's will fit? Does anyone have any first hand experience with this or any pictures?

Other than the looks, what are the other advantages/disadvantages to going with 16's? Any I going to get wheel rub in the inside front fenders when I turn hard? What are the tire selection differences?

-Britain

[umgang]

Having just gone through this with my 1975 911S3.6 I will share my experiences. If you want to retain your narrow body and fuchs wheels and run lower profile or wider than 205/60-15, you need 15x7 (R) wheels or 16x7 (951) wheels. Both of these types have a 138mm backspace rather than the stock 112mm. This allows for the additonal inch in width to go to the inside of the fender rather than out to the fender lip. I've been running 205/60-15 front on 15x6 stock wheels; and 215/60-15 on 15x7 (R) wheels rear with no rub problems. Recently with a major suspension change I need lower profile and wider footprints so I bought 4 16x7 (951) 's and put 205/55-16 front and 225/50-16 rear. My car has wheel spacers on the back so inside of tire doesn't rub on oil cooler lines running to dual oil coolers in front wings. 16" wheels offer a lot more tire choices, are slightly heavier, and the 951 wheels tend to have blacked out centers, but you can refurbish them. The 15" wheels retain the traditional fuchs look, are lighter, but tire choices are very limited (depends on what you want to do with the car). 951 wheels from 1986 944 turbo are not as hard to find or as expensive as the 15x7 (911R) wheels. Hope this helps.

[ubiquity0]

FYI the offset (& backspacing) for 951 7x16's is identical to the 911 7x16's. The only difference is that the spokes on the 951 rims are configured to clear larger brakes.

[Britain Smith]

I was looking into tire sizes and I think that I would be happen with a set of 205/40/16's on a set of either 6's or 7's. This size is actually slightly lower in total diameter than the 205/50/15's.

So, umgang, you car is a narrow body and you have no problems fitting the 7's on the rear? Do you have to run a lot of camber or anything to keep the outside lip from rubbing?

-Britain

[umgang]

No problem fitting either 15x7 or 16x7 but please note my prior thread-backspacing is the key with narrow body. Also, you will find most tire suppliers will call out a rim width range of 6.5"-7.5" with an advised 7" rim width for any 205 lower than 60 profile. Ubiquity0 I respectfully disagree per 911 Fuchs wheel data: (951) 7x16s have a 23.3 0ffset, 138mm backspace P/N 951.362.115.00; 911 7x16s have a 23.3 offset, 112mm backspace P/N 911.362.115.00 For more info on tires scan the "tires by size" and "specs" section of www.tirerack.com For a copy of the above fuchs wheels spec data go to www.rennsportsystems.com and look in Steve's library or Porsche Technical book.

[PcarPhil]

I'm awaiting a set of 16x7 Fuchs for my '71 911T. I have a feeling I'll end up refinishing the wheels before I install them so it may be a while before they're actually on the car.

I'm planning on running 205/55/16, 205/50/16, or 215/45/16 tires on all 4 wheels. The tires will be Toyo T1S or Falken Azenis.

-Kaefer

[ubiquity0]

Originally posted by umgang
Ubiquity0 I respectfully disagree per 911 Fuchs wheel data: (951) 7x16s have a 23.3 0ffset, 138mm backspace P/N 951.362.115.00; 911 7x16s have a 23.3 offset, 112mm backspace P/N 911.362.115.00 For more info on tires scan the "tires by size" and "specs" section of www.tirerack.com For a copy of the above fuchs wheels spec data go to www.rennsportsystems.com and look in Steve's library or Porsche Technical book.

Umgang- are you sure? If the wheel width remains the same (7") and the offset is the same, then how can the backspacing be different?



Could some of the wheel data be erroneoulsy quoting the backspacing for the 951 8x16 wheel (951.362.117.00) in place of the 7x16?

IMO the 911 & 951 7x16s should have the same fitment paramenters (except brake clearance). Interestingly some have reported that the 951 8x16 can potentially fit the rear of a narrow body 911.

[RoninLB]

Originally posted by umgang

4 16x7 (951) 's and put 205/55-16 front and 225/50-16 rear. My car has wheel spacers on the back so inside of tire doesn't rub

so if you would have run the 205/55-16 on the rear you would be ok with stock rear alignment, no spacers, and no rub? And same for front stock alignment and rub w/ 205/55-16 ?

TIA

[W Scott Shores]

My '71 911E sports 16x7 Fuchs on all four corners. Tires are 205-55-16. I experience slight rubbing at the front when turning at low speeds (parking lots, etc).

205-50-16s might solve that problem...

[Todd Simpson]

Why would you want to use stock alignment? Even for street driving 1 to 1.5 degrees in the rear will increase grip with minimal wear AND help you avoid tire rub.

16x7's will go on the rear with 205/55's. Test fit prior to driving, if they are going to rub it will be about 2 inches above the fender lip. You can easily burn the paint there, it gets ugly quick. 225/50 has been done, but only with 3 degrees of negative camber.

205/40's would look downright silly too, not nearly enough profile.

Bill Verburg's wheel page has the same backspace for the 951 and 911 7x16's. I don't know how the offset and width can be the same with different backspace.

http://members.rennlist.com/1976c38/index.html

[umgang]

Backspacing is the distance between the inner hub mating surface and the outer rim edge. The 15x7 911R wheel, P/N 901.361.012.05 were special in regard to their width and offset or backspacing. The 911R wheel had 130mm ( 5 1/8") backspace as compared to 125mm (4 7/8) for other fuchs wheel of the day. Agreed 2" camber in rear would be advisable for 205/50-15.

[Plavan]

umgang,
What size spacers are you running in the rear? Did you have to get longer studs?

[911S Targa]

I just bought some 16 x7 to go on my rear. I put 225/50's on, and Im rubbing, even after camber adjustment. Should I have gotten a lower profile tire ? Like 45's instead of 50's? Or does that even matter.

[PcarPhil]

Originally posted by 911S Targa
I just bought some 16 x7 to go on my rear. I put 225/50's on, and Im rubbing, even after camber adjustment. Should I have gotten a lower profile tire ? Like 45's instead of 50's? Or does that even matter.

I've been wondering about that myself. I haven't gotten my tires yet so I think I'll go with 205/50/16's and 225/45/16's.

Where is the rubbing?
-Kaefer

[911S Targa]

Originally posted by Kaefer
I've been wondering about that myself. I haven't gotten my tires yet so I think I'll go with 205/50/16's and 225/45/16's.

Where is the rubbing?
-Kaefer

The rubbing occures while under heavy load going into right hand corners. The left rear rubs more then the right rear, but I think my weight has something to do with that. I had the right rear fender lip only rolled, so its not chewing up the tire, but they didnt do the driver side, because of chipping the paint. So now I need to get the lip rolled on the drivers side. Once I'm up to speed, and going into corners, I dont have an issue. Seems to be rubbing on the top part of the rear fenders. I run 205/55's up front, and I have zereo clearance problems. The rears are whats giving me a headache. Granted, I've only driven about 14 miles on these new tires, I dont want to chew these up, if I need to change the rear tire size, so at least I can turn around and sell these.

With the right backspace, 16x8's with 255/50 rubber will fit.

[Wil Ferch]

Umgang:

your numbers ar wrong....

See here--->
A 7" wheel is 177.8 mm.

With a 23.3 mm offset, this would equate to a 112 mm backspace....NOT 138 mm backspace. ( 177.8/2= approx 89mm at the mid point. .....Add 23 offset= 112mm. Checks.) I want *all* of us to think about this...HOW CAN TWO 7" WIDE WHEELS HAVE THE SAME OFFSET BUT DIFFERENT BACKSPACE ????

All 7" are the same backspace and offset....only the 951 is built with more clearance for brakes...a completely different proposition.

- - Wil

EDIT:
for proof..see here--> http://members.rennlist.com/1976c38/index.html


Wil

[911S Targa]

Here is a pic of the fronts.

The fronts with 16x6, running 205/55/16 SO3's

[911S Targa]

So my issue is, which should I be concerned about to fix the problem ? The section height,tread width, or section width.

[PcarPhil]

With the wheels you have I would say you need to be concerned with tire height,ride height, camber, t-bar rate, and possibly rolling/pulling the fenders even more.

Or custom offset wheels like in Mark's pic.