true rear coilover conversion

[topnotch]

Car:
1994 BMW 325is
track oriented, gutted
expected completed weight of 2300lbs

Current suspension:
KW V3 Coilover

So i'm rolling around the idea of running a true rear coilover, i am already familiar with the advantages and disadvantages of doing so.

My questions is if there is any kind of sleeve/collar made to run 50mm springs over the KW rear shocks to convert it to run a true coilover? (similar to the AST's set up maybe?) I've searched around and cannot find anything. Any ideas on who might have them or who to contact would be appreciated.

One note; i am not going to get rid of the KW coilover set up at this time - simply just looking for ways to convert the rear to true coilover.

Thanks,

Tim

[nighthawk328i]

While it may be possible, I would definitely be concerned about the rear shock mount. They tear through with just a shock there. If you add the force of a spring too I think you will see a very fast failure. The only way to remedy that would be to tie in a cage to the rear towers or weld in some form of reinforcement.

[topnotch]

While it may be possible, I would definitely be concerned about the rear shock mount. They tear through with just a shock there. If you add the force of a spring too I think you will see a very fast failure. The only way to remedy that would be to tie in a cage to the rear towers or weld in some form of reinforcement.

My build thread shows reinforced rear shock mount towers - i might do more if i end up going with a true rear coilover, but, at this time i am not concerned with the rear coilover punching through. Just looking for the parts to make it happen.

[Toby Larsson]

I did the conversion a few years ago using Penske DA's with 2.25" springs. The only way I could get the spring to clear the inner fender was to run the shock inverted. You might be able to clear with a 50mm spring and the shock in the standard position but I doubt it. Can the KW shock be mounted inverted?

[topnotch]

I did the conversion a few years ago using Penske DA's with 2.25" springs. The only way I could get the spring to clear the inner fender was to run the shock inverted. You might be able to clear with a 50mm spring and the shock in the standard position but I doubt it. Can the KW shock be mounted inverted?

Not sure if i can mount them inverted - then i'd have to cut the eyeball off the shock and fabricate a RSM. I'd prefer to run 50mm so that i can clear.

[Toby Larsson]

Not the greatest pic, but it shows how close the spring sits to the inside sheet metal.

[jmitro]

I had to clearance the inner sheetmetal just a bit as shown by Toby above.

to reiterate a point made above, the shock towers will see significant force. if you don't have a cage tied into the shock towers to direct the loads, I wouldn't rely on reinforced mounts alone to support the car's weight IMO

[topnotch]

I had to clearance the inner sheetmetal just a bit as shown by Toby above.

to reiterate a point made above, the shock towers will see significant force. if you don't have a cage tied into the shock towers to direct the loads, I wouldn't rely on reinforced mounts alone to support the car's weight IMO

thanks, and like i said above - i would reinforce the rear shock mounting points if needed.

[fifth]

Things Ive learned about rear coilover..

-spring rate runs about half of the front

-if you slot the rear top hats, you can slide the shock over so it does not rub the inner fender

-upgrade the lower shock bolt (arp maybe)

-need a small shock in order to not bottom out the shock

[topnotch]

-need a small shock in order to not bottom out the shock

What extended/compressed length do you think is the best fit? I've been looking at some made by QA1 - and i have quite the range of options. I'd only run the QA1's if i cant find a collar/sleeve to fit on the rear shock.