gruffalo

my pass side front wheel sits about 10mm further back than it should do.

the front suspension has been completely rebuilt by a PO.

what kind of mistakes could have caused this?

a blend og post '86 parts and OB parts perhaps?

MM

Jim M.

Both the upper and lower suspension supports are permently located on the sub-frame. Therefore, previous body damage with incorrect frame straightening is the most likely cause. Or, you could have a bent spindle, but I think that would cause lots of other problems that you would have noticed first.

One other point; Porsche says that all body measuring points are plus or minus 10mm. So you may be within factory specs.

Jim Mayzurk
93 GTS 5-spd

gruffalo

I have checked for body damage, and find absolutely no sign of that. I'll have to do more measurements...

SharkSkin

See if your lower ball joints are oriented in a symmetrical fashion. If one is cocked forward and one is cocked rearward it could account for this.... Otherwise start looking for bent mounting points/a-arms. Lots of front A-arm pivots get mashed by steep driveways.

GlenL

There's also some fore/aft adjustment in the rear tranny cradle.

IcemanG17

Odd...sure sounds like a bad wreck sometime in the past?

928ntslow

First thing to determine is what are the reference points you are mesasuring from???

Go to an alignment shop and have them check the caster on both front wheels. This is most likely your problem.

If the rear crossmember that holds your tranny and wheel carriers, etc, was removed, it may have been possible that the person who did the work, did not mark the cross memeber location for re installation. The crossmember bolts to the under body and is adjustable fore and aft.

This is one of the beauty's of the 928!!! Four wheel adjustment!

GlenL

Bad wreck? 10mm is nothing.

Also, Gruffalo, how'd you do the measurement?

gruffalo

I got it. I have one alu lower balljoint (yes, I will replace) and one steel. The steel one is not mounted straight on the arm, it's bent backwards. I do not think the steel one has the correct hardware (excentirics and so on).

The right side one is WAY different, the difference in posision is equal to the size of the nut when I measure it, with reference to the lower arm.

I'm probably up for the alignment job from hell when this is fixed.

When replacing and re-mounting the lower ball joints, how do I position the excentrics to start with? To get it roughly as correct as possible?

SharkSkin

Capt. Earl has a great page on alignment here: http://members.rennlist.com/captearlg/928align.html

Might want to have a close look at other parts on that side -- if the Alu. carrier broke while driving other parts may have been bent/stressed and not repaired by the PO.