Bilstein HD rear lower spring perch height help, Recommendations for lower spring perch setting on bilsteins Options

[Krohn]

I'm finally at the fix the severely sagging rear springs project for my car, and am wondering if there's any guidance on where to set the lower spring perch for the new rear Bilstein shocks?

I'm keeping the car as sock as possible, think of me as a James May if you must, so I have a new set of stock ride height springs (85 lb) and the new replacement struts. Comparing the old and the new side by side, it almost seems that I need to move t he circlip all the way to the top on the new shocks... but that seems almost crazy! Since I'm aware that the new springs, at 85 lbs, are heavier than the originals (maybe 70?), would it be better to move the perch down one relative to the old shocks?

Old springs/shock on the left, new on the right
(IMG:http://www.914world.com/bbs2/uploads_offsite/1.bp.blogspot.com-18091-1555182313.1.jpg)

Any advice or recommendations out there?

The stock rear sway bars stay (front and rear), which was also a driving motivation for keeping a lighter weight spring in the back.

Maybe it's time for a project thread... but progress is piecemeal and slow, so it might drag on, and on, and on...

Thanks!
Robert

[Retroracer]

I have the same springs as rgalla9146, 2nd from bottom gives me similar ride height to his car. Much fiberglass, battery relocation lighten the rear - 2.2l six in my car - but strengthening panels and roll cage add to the mass. Even altering front height may affect the rear slightly.

In other words: there are many variables at play, basically you should start with "best guess" and be prepared to alter if needed.

- Tony

[rgalla9146]

I have the same springs as rgalla9146, 2nd from bottom gives me similar ride height to his car. Much fiberglass, battery relocation lighten the rear - 2.2l six in my car - but strengthening panels and roll cage add to the mass. Even altering front height may affect the rear slightly.

In other words: there are many variables at play, basically you should start with "best guess" and be prepared to alter if needed.

- Tony

Tony your last sentence says it all.
I trailered my car to the alignment shop after it was driven maybe one mile.
Driving out of the parking lot I looked over my shoulder and realized
the rear of the car looked too high.
It was sitting on Konis all around. No rear height adjustment possible........
.......back onto the trailer.......change all four corners to Bilsteins and do a
trial fit with the perch set as pictured. I got lucky.
It could have been a few remove/install cycles.
Be prepared.....you might have to do it over.