Lowering Questions??

[vesnyder]

I have an '83 SC and just lowered the front about an inch to 25" (measured at the fender lip). Wanted to lower the back as well but could not get the bolt loose? The car rides very nice outside of the bottoming out on my driveway! Several questions:

- How can I loosen the bolt to lower the back?
- After lowering the front how critical is a front end alignment - it rides and tracks fine?
- What does bump steer feel like? Are there varying degrees? At which point do you need to install the bump steer kit? Is it more prevalent on aggressive driving?
- Will new shocks prevent some of the bottomong out?

Any other suggestions/modifications?

Had it up to 120 MPH this morning (early!) and it hugged the road. Not a real experienced mechanic or speed junky and in retrospect maybe not the smartest thing to do after I have been making suspension modifications?

Thanks in advance.

[marcesq]

Vance:

There are 2 bolts that require loosening on the spring plate before the rear can be adjusted, assumming that they were assembled with the cam adjuster in the middle.

I had to to take my spring plates to the shop to have the bolts broken loose, but I had them off because I was replacing the bushings. Get a 6 sided 1/2" socket and a pipe as long as you can fit over a breaker bar. Then gradually apply as much pressure as you can. You will need a thin wrench (24mm & 36mm) to reach the rear of the adjuster bolt and the set bolt.

The shocks should not effect ride hieght and therefore ground clearance.

The lowering of the car will not effect alignment, but might have an effect on camber.

Bump steer occurs due to change in the tie rod angle from level as compared to the ground when a car is lowered. Check with car on an alignment lift or other lift that maintains weight on the tires.

The bad news is that after lowering the car, you will need a good corner balance.

Hope this helps.

[k9handler]

looking at the same issue, but I guess I jut don't see how this is done.
Anyone have a picture/step-by-step guide?

[Vipergrün]

You can purchase the thin 36mm wrench at a local bike shop for about 12.00 or so. May be able to get the 24mm as well.

I have a write-up on the lowering process, but not many specifics on adjusting via the eccentric bolt. Can be found at: members.rennlist.com/bb79sc

You basically need to loosen the *upper* bolt first as it acts as a *hinge*. Then, loosen the nut on the eccentric bolt. Get the 36mm wrench on the head of the eccentric bolt, between the back side of the spring plate and the wheel well. Helps to have the car off the ground when doing this. The eccentric bolt allows approx 3/4 inch of adjustment. Adjusting the lower-end of the spring plate *up* lowers the car.

With the front at 25.0, you probably want the rear at 24.5. Euro spec is 25.0 rear and 25.5 front from the ground to the top of the arch of the fender. Need to keep the car at the proper attitude.

I'd highly recommend installing a bump-steer kit from Pelican. Only about 15.00 and installs in < 1 hour. This gets the tie rods closer to parallel and really helps with the *kick back* in the steering wheel.

Have fun, and good luck.

cheers
-Brad
80SC

[marcesq]

HD:

The main reason that you can't "see" it is because your car does not have the adjustable spring plates unless they were added after the car was first purchased.

Adjustable spring plates were first installed by Porsche in '77.

Of course, someone might have added the same.

There is tech article in Pelican Parts' 911 section on this issue, I think it has some illustration.

[k9handler]

Thanks Marc...I was wondering what was up? Now I know. I do have the front at 25.5 and the rear at 25.0, so I guess that's not to bad.