rbcsaver

I will try and be as susinct as possible, but I need help!
My 84,911 with 128K miles, was new to me in 1995. Never in an accident,that I know of.
A couple of years after buying the car, I had it lowered. The Porsche dealer stated that they had one heck of a time, "was the Right(passenger's) Rear(RR) trailing arm bent?" I didn't even know exactly what the training arm was back then. New Bilsteins, all 4's at some point. A few years later, the left rear T-Bar snapped coming out of turn 5 on the Jefferson Circuit, Summit Point. No spins, contact etc. Trailered the car home. I had used 930 T-Bars(26 or 28s) installed and another alignment. On alignment, they lowered the car more, to the height on the picture. Again posed the question about a bent trailing arm.There is no damage aparent to same, so again I attributed the issue to same dealer, same technician (in reality,perhaps not the same guy) It has been pretty good, though tends to (prematurely) wear the inner aspects of front and rear tires. Negative camber is may understanding. Wheels are 7s and 8s X 16" (plus spacers) 944's(sold to me as 911 wheel) when I was less informed, shall we say.
Over the year I have personally performed the following suspension "upgrades" with parts from Pelican and Performance.
(no significance of the order)
1. Bump steer kit (Perfomance)
2. Turbo tie Rod Kit
3. OEM 930 F&R Sway bars and OEM rubber bushings
4. 22 mm Front T-Bars
Then front alignment was adjusted by a local Non-Porsche shop after the above was done and all seemed OK. With limited miles, I noticed that the inner aspect of the rears was, again prematurely worn-out and required new tires to pass inspection. The fronts were starting to wear more as well on the inner aspect. So I put 245/45/16 Dunlops on the rears and 225/50/16 on the front. I noticed rubbing on the RF side. I measured the wheel well height and noticed the the Right side of the car was 1-1.75" lower than the left. You can see how low my car is from the pics (***note that the pics are with 225s rear and 205's front.)
I had planned to replace the ball joints, so I proceeded with that bear of a project. I dropped the car at a different dealer last night.

The bad news today:
I will attach the e-mails I received from the dealer in quotes after the specs I received from the shop manager, with the **BEST** numbers that they could get::

Spec REAR Camber: -1.2 degrees

Mine: RR: -3.9 degrees, LR: -1.7 degrees

Spec FRONT Camber: -0.2 degrees

Mine: RF: -.7 degrees, LF: -0.4 degrees

Rear Toe: Spec 0 degrees

Mine: RR -.12 degrees, LR: +1.03

The shop manager did not know how much I need to increase the bump steer, which he explained as a lack of knowledge about the older Porsches. Keep in mind that it cost me $240 today for them to level my car, keeping a similar height in the pics but now a "confirmation" that my RR trailing are "maybe" bent. Also a question about my bump steer kit from Performance being high enough..though they couldn't give me an appropriate shim width. How much more (if at all) can I shim from the Stock Bump Steer kit?
He mentioned an adjustable trailing arm kit which would "compensate and allow for fine tuning" of the bent side, but it seemed again like his knowledge base on the older P-cars is small.

"Front....tie rods are on a major upward angle.....very bad....should raise the front rack and straighten these out. This is what is giving you very bad bump-steer and the wondering effect....cause it is....the front end just wonders."

and

" Also, the RR wheel alignment is so far off, it appears that the trailing arm is bent. The only way to be sure would be to disassemble the torsion bar assy. and return the ride height to stock to verify to proper angles, this will be costly. The other option is the installation of an after market rear trailing arm kit, this may allow more range of motion for fine tuning the alignment. We were able to raise the rr to be even with lr, but the rr camber and toe is way out."

Please some Help and Suggestions from the great Steve Weiner and others on how to proceed and get my Street Car with an occasional DE/AX event. Unfortunately, I'm not in Oregon, But PA. ARRGH!

regards,
Steve
rbcsaver@ptd.net

Steve Weiner-Rennsport Systems

Hi Steve:

Hey,...Oregon is just a nice drive West,...

On to your problem,.....

These kinds of things can be very complex to resolve from such a distance and I must (dangerously) assume a level of knowledge and competance on the part of the alignment shop here.

First, your car is too low in the rear. You didn't give any ride height figures, but that picture shows the right side is a good 1.5" too low. When these cars get too low, the geometry falls off and any bent or misaligned suspension components really show themselves.

Second, get the car back to the proper ride height as dictated by your stock length shocks and set the height with a 1 degree nose-down rake.

I'd venture that you have one (possibly two) bent rear trailing arms (the alloy ones) to varying degrees and you never align the car properly if they are bent. This is not uncommon at all. Porsche intended for these to bend and thus absorb any deflection to protect the chassis from damage in the event of a collision with a curb.

There is no such thing as a kit to compensate for bent trailing arms. The weld-in, race-type camber boxes are intended to give race cars easier and greater range of alignment.

Steve, IMHO you need a complete chassis setup by setting the car to a proper ride height and then determining if anything is bent and out of spec. Only then will you know what needs to be replaced.
Your suspension component choices are basically sound and all you really need are these things to be properly installed and setup.

Please call me if you have any questions about this.

BTW,....Front tie rods must be close to level to minimize bump steer. One does this with the rack spacer kits. Since the available room under there is somewhat limited and the rack cannot be raised more than .5"-.68", we use the ERP Bump Steer kit which is a pair of adjustable tie-rod ends to replace the OEM ones. These permit the tie rods to be spaced up level and enable very fine bump steer correction on each side.

You can see a pic of these things on the ERP page of our website.

J.G. Rausa

Steve:
You might try Dwight Foster. He is knowlegeable and has the correct alignment equipment. He should be able to offer a recommendation.
Regards,
Joe

rbcsaver

Joe,
Spoke with Dwight on the phone and he has has good taken care of me. He's going to pick up the car from the dealer and fix it!

Steve