Need diagnostic help - Bizarre wheel rubbing "85 Carrera

[Allan Kelsey]

I switched my factory 16" Fuchs wheels for a set of previously loved BBS 17" that are factory approved offsets and appropriate tire profiles for my staggered 215 & 255's.



Even before I changed out the wheels I noticed my drivers side wheel had a different wheel to fender gap than the passenger side, however now that the larger wheels are on there, the drivers side tire, rubs ever so slightly under load on the fender lip.
Compare the right & left sides by looking at the amount of tire that protrudes from the fender at the line that separates the bumper from fender. There is a 15mm difference!!

Here's the passenger side:




Here's the rubbing driver's side:




Im open to suggestions????

PS//I have double checked that the wheel offsets are correct and matched left to right.

[Oh Haha]

Your 17s are bad, I 'll take them off your hands in the name of your safety.





Just kidding, obviously although they do look good on your 911 and mine is the same color.

The rubbing may be simply due to the different brand of tires(if so) on the 17s vs the 16s. Different manufacturer's tires are slightly taller/wider/narrower than others even the size is the listed as the same. I would be willing to bet the 16s are just a hair smaller in diameter and width.

[tshebib]

All our cars are built with this discrepency, It's Porsche's dirty little secret. You'll need at least 2.8 deg of negative camber in the rear or this can happen.



The right side is no where near the fender just like yours.
I'm running 17in, Rota's with 255 tires, 29mm torsion bars and 22mm Tarret sways maxed out. The rear height is at 23 3/4 in. to the fender lip. I started out with 2.8 deg and after a day of lapping the rear camber changed to 1.5deg??
I'm getting it painted this week and reset the camber at 3.3 and used a power bar to tighten the spring plate bolts this time. fingers crossed. I could raise the ride height but it looks and feels so good at this level.

[msterling]

I don't think that it is unusual for a hand-built 911. You could roll the fender lips or run a little more negative camber. Do you have spacers on the back? Also, Porsche didn't anticipate that owners would lower their cars so much.

[Allan Kelsey]

Oh Haha,
Yes, I think you are right.... must be a safety issue....

tshebib,I did just have the alignment reset, but I have to believe that this is not normal.
Could the motor be off-center (pushing the driveshaft closer out toward the wheel well) perhaps from an undisclosed accident from previous owner?

[msterling]

Like tshebib said; these cars typically do not have the running gear centered with the rear fenders. When you start running wider tires and lowering the suspension it becomes apparent. My car is the same way. The driver's side rear tire sticks out farther. My goofy setup is not close to the fender lips as I am running 15" wheels with 225 width tires.

What width and offset (ET) are your rear wheels? As an example, my original equipment rears are 15x8 ET 10.5 Fuchs. Same bodywork and rear suspension as your car.

Yes, your car could have been bent by a previous owner. A good alignment tech would have noticed this when aligning the car.