This past weekend I did a bit of hacking and welding on my suspension in my quest for a low stance. Since the rear suspension is a true coilover system,my need to go lower is a simple adjustment of the lower spring seat. The front suspension is a different story. The BMW E34 uses a McPherson strut that incorporates the hub assembly into the same unit. Because of the fact that the front brake rotor, hub, bearing, etc. is removed all together as one unit when servicing the front struts, most aftermarket suspension manufacturers chose to re-use the OEM strut assembly. A threaded collar just above the factory spring seat allows for replacement or aftermarket strut cartridges to be installed into the same housing.
What does all of this have to do with my wanting a low ride height? Well my coilover kit uses a threaded, height adjustable sleeve that also has threads on the inside. This is used as the cap that threads onto the strut housing, locking the strut cartridge into place, yet also providing an adjustable spring seat. This with the use of a shorter free-length, and smaller diameter spring makes for a compact, adjustable package. The catch is too use these front coilovers in the fully down position, the factory spring perch must be removed for clearance of the new spring perch as shown here:
This of course was not low enough for my taste. Though the rears are currently only half as low as they could go. The fronts are as low as they can go. At this point I decided to modify the housings a bit, allowing me to go lower without sacrificing suspension travel or ride quality.
As you can see in the picture above, I took a 3/4″ section out of the strut housings, wihc in turn loweres the entire height adjustable section of the coilover units. I decided to cut out the section of the housing where the factory had MIG welded the OEM spring perch. Since this area had already been stressed from years time, I decided to omit that particular section of the housing instead of cutting somewhere else. I then TIG welded the two sections of the housing back together.
However shortening the housings would be of no use to me unless I had shorter strut cartridges as well. Fortunately for me this kit uses a much shorter than factory cartridge, made for a shorter stroke. These shorter units have a built in “stem” at the bottom so they sit at a correct height within the strut housing. The stem is solid metal and just acts as a spacer. Because the stem has no real use, I was able to take a similar 3/4″ section out of them to make everything sit lower in the newly shortened housings. In the picture above you can see the shortened cartridge on the left, with the unaltered unit on the right.
By the end of the night it was pouring rain. I ended up adjusting the rear suspension down another inch, installed my new exhaust, and called it a night. The bottom-most picture above was taken the day after, once the rain had turned into snow, and the springs had settled back down. Overall I’m finally happy with the ride height and can move onto bigger and better things for the car.
I have a set of 7-series side skirts I plan on sectioning to fit E34’s, still need to finish my full projector headlight conversion, and am trying to source a blower for the car as well. The future is still bright for this E34, but it all takes time.