Why is there more room on this side than the other?

Won · 01:44 AM

Today I noticed something very weird. From the behind, the driver's side rear wheel seemed to stick out more than the passenger side. Same tire, same pressure, but they definitely looked different. Upon further investigation I discovered the vertical section of the fender extension that follows the bumper outline is no longer vertical, instead the bottom was somehow pushed out. I tried to stick in a water bottle in the gap between the tire and indeed, there's a lot more room on the passenger side than there is on the driver side. The passenger side wheel was sitting about half an inch deeper in the wheel well. As far as I know the car was never in an accident. How could this happen?

It took me 4 hours to figure it out: The second night after I got the car, I changed the brake pads. Lifted up the rear, jack stands under the torsion bar covers, took off the rear wheels, changed the pads. Then I lifted up the passenger side using the factory jack and wiggled around to put the wheel back on when all of a sudden the car just rolled forward. Next thing I know, the entire rear end of the car is supported by the passenger side fender that is resting on the tire. It freaked the hell out of me, but with a couple scissor jacks from other family cars, I lifted the rear end up, and put the wheels back on, and everything was fine. Yeah right. Apparently that bent the rear fender and the quarter panel, so much so that now there is an extra half an inch of flare on that side. How cool, eh?

Two things: now I always block front wheels whenever only the rear end is up in the air, and I wonder how I managed to get my fingers or arm out of way when the fender landed on the tire. If I ever decide to put wider wheels, I'm just gonna have to drop the car on the other side so I can fit equal sized tires. Maybe I'll do that until I get the 10" Yellowbird flare in the back. Do you think I can "fix" the driver side with a fender roller?

By the way, the car drives straight, brakes straight, cambers look equal enough and tires wear at the same rate (the closer you are to the wear bar, the easier it is to track tire wear), so as far as I'm concerned the car is still straight

oldE · 05-01-2006, 01:50 AM

Won,

Most of the guys who do bodywork on these cars will tell you there are usually differences between one rear fender and the other. Guys have built specialized tools for stretching fenders to get proper clearence.
Glad to hear you got your lesson on wheel chocks with nothing more than a scare and some embarassment.
The only way to tell if the car is straight is to check it out on an alignment rack. Having said that, if you have no tire wear or handling ussues, I wouldn't worry about it.

Les

Driver8 · 02:26 AM

Won,

That is the joy of a hand built car. I don't believe that there are too many 911's that do not have some sort of fender misalignment, or height difference from one side to the other. Next time you are around some 911's take a good close look and you will see that your car is not the exception.

Wil Ferch · 05-01-2006, 08:02 AM

Has nothing to do with being a "hand-built" car....( BTW...911's were largely hand assembled and not hand "Built" in the old Ferrari or Brit way)...

If that was the case of being hand built...we'd be seeing variability....

There is however, no doubt that the "master" from which all 911's were based-on.... may not have been symmetrical ...left to right. So...with precise manufacturing methods, this "minting error" gets repeated in all 911's....

As a data point...if there is a possible tire rub with oversize tires...it's usually the LF that's the culprit...for the same reason.

- Wil

Zeke · 05-01-2006, 08:33 AM

Quote:

Originally posted by Wil Ferch
Has nothing to do with being a "hand-built" car....( BTW...911's were largely hand assembled and not hand "Built" in the old Ferrari or Brit way)...

If that was the case of being hand built...we'd be seeing variability....

There is however, no doubt that the "master" from which all 911's were based-on.... may not have been symmetrical ...left to right. So...with precise manufacturing methods, this "minting error" gets repeated in all 911's....

As a data point...if there is a possible tire rub with oversize tires...it's usually the LF that's the culprit...for the same reason.
- Wil

Or, LR, in the case of a narrow body.

Will, your postulation is a litte hard to swallow. However, I don't have a better one....

Wil Ferch · 05-01-2006, 08:52 AM

Why is it hard to swallow.....the 911's were pretty much factory assembled..look at archival film footage how these cars were made, there was a lot of hand fitting for example on the door leading edge using molten body putty, etc....and there was a lot of tin-snipping going on to make the rear window flange work...but for the most part, these were hand assembled...not hand "built" cars.

There was no guy forming a fender on an English wheel from sheet stock....these were "pressings"...and fairly accurate presings too.

The 356 had a RR tire clearance problem...the 911 has a LF tire clearance problem...the cars were not symmetrical left-to-right on the master that was used for subsequent production. The lack of symmetry carried over pretty much car-to-car....you will not see random "variability" as if the producton tolerances were loose or when "hand-formed" body panels were used. This "hand-built" stuff is a myth we like to perpetuate.

I'm not saying that *this* fit-up represents *this* facet....but it did exist as a general comment .

Even old-man Ferry ( Jr.) often went to preview "new" models in the clay shop before they were introduced...and would sight-down the length of the car and say ( at times) the cars weren't identical on both sides.

- Wil

nesslar · 06-13-2006, 02:33 PM

Driver8,
Your post of May 1st should be read by every owner who has ever even imagined little such differences. I believe many of the whole of Porsche 911 owners would be feelin' a lot better knowing that these machines not only exhibit little diff's but also are mostly older, and track runs, gravity, age, etc., all do their thing over time, do they not?

'86 Guards Red Targa, with slight "diff's"

And it goes straight down the road under power,
and while braking......
...except in corners...

RPKESQ · 06-13-2006, 02:47 PM

Wil, this misconception happens all the time. Hand built means, every part is made by hand (no automation, no parts interchangability), hand assembled means mass produced parts are carefully fitted together. I apprenticed as a gunmaker in the UK and learned to "hand make" the parts needed for a proper side by side. Hand made is seldom seen anymore today!

afterburn 549 · 06-13-2006, 03:24 PM

you will find this to be a reg.patern in the 911 world, nothing to be concerned over.

cstreit · cstreit's Garage

Yep... Usually the drivers side has less fender clearance than the pass. side. Normal.

Jack Olsen · 06-13-2006, 03:31 PM

Your speedometer is probably optimistic, too.

Won · 06-30-2006, 01:00 AM

Recently I bled the brakes and had a chance to measure the distance from the frame (inner fender wall) to the fender lips on both sides, and they were the same. My LR tire still sticks out half an inch farther out than RR one, and from what I've seen on other cars, 7 inch Fuchs in the back sould sit right where my RR is at now. Hmm.

Paulporsche · 06-30-2006, 04:33 AM

Try measuring the frame to the hub (wheel carrier). Also try checking or temporarilly swapping your rear wheels.

lateapex911 · 06-30-2006, 07:10 AM

On my car, it's the opposite. Plenty of room on the left, way tight on the RR. No signs of an accident. The difference is way over a half inch.