I just replaced the rear shocks on my 1980 928 with Konis, and took it for a drive. Everytime I give it any gas the car darts to the left. I still have to dial in the ride hieght, and get an alignment, but it feels very strange like the right rear is squating, making the car dart left. Could this also be from the two shocks being adjusted at different stiffness settings? This might be the case, but I have no way to tell. sway bar, and drop links are all good, and intact. Any advice will help. Thanks.

 

I suspect you have an alignment issue. It's called thrust angle where the net toe (right plus left) pushes the rear of te car one way or another. I had this too and the alignment made it go away. Get it done soon or your rear tires will scrub away in a matter of days.

 

or you could have two different sized rear tires and limited slip.
Sounds like andrew has nailed one probable answer

mk

 

thanks, that makes sense that it would be an alignment issue.

 

You didn't torque the lower shock mounting nut to the correct spec.
Try it again.

 

Sounds like you inadvertantly converted it to front wheel drive.

Seriously, you have gotten a long way from the basic set up. Check the torque on all shock mounts, adjust your ride height and head for an alignment shop that is familiar with the 928. Anyone else is guarenteed to make matters worse.

 

Did you remove the lower pins( the thick pin that the lower shock is mounted to) and check them for true by rolling them on a smooth surface? If you didnt, then you should, before you get the alignment done, also check the ride height, plus see if the lower control arm eccentric is loose where it bolts to the unibody. Did the beveled washers get put back in the correct position?

 

Or you didn't stack the spacers in the correct order/orientation.

I had the same issue with my car long ago. I even checked the lower nuts for tightness with a box end, just to make sure they weren't loose. They were snug with the box end. Wally P. said it was the nut, so I went over it again with the torque wrench. Sure enough, probably got another half turn on it. Problem solved.

 

The shocks should have been set at the same point in the adjustment range before you installed them. If these are standard Konis, and not converted to externally adjustable, then you compress the rod fully. It will engage a cam. IIRC, it is about 2 1/2 or 3 turns stop-to-stop, with clockwise being hard and counterclockwise, soft. You can buy a tool for adjusting them on the car after installation - you loosen the top center nut and insert an elongated Allen key into the end of the rod, push down to compress the shock fully, engage the cam and adjust as mentioned.

Koni shock tool:
https://www.928gt.com/ps-26064-128-koni-shock-tool.aspx

Others have mentioned the assembly order of the washers on the lower pin. There are two conical washers - the cone of each fits inside a recess on each side on the hub carrier. There is one more flat washer on the other side of the shock and bigger flat washers on each end of the pin under the nuts. The nuts on the end of the pin must be tightened to 103 ft lbs.

 

Thanks for your help guys. I just tightened up those bottom shock bolts, and the car tracks straight now.

 

Cool. However, you should still monitor it and get it aligned if you notice and rubber dust on the back of the car.

 

already scheduled an alignment, since I swapped out the front shocks as well.