Note: if you have not read my previous post, I suggest you start with the Part 1.
Because This was my third E30, I already knew how challenging this small boxy bimmer can be with both suspension and tire setups. On part one, I was able to correct some of the suspension geometry challenges by installing custom made raiser plates.
There was still too much negative camber on front tires, though raising fixed the issue on rear axle. The solution for front tires was to move upper strut outwards. Typically you have two options: either install an adjustable uniball strut mounts or select a fixed one. The advantage of uniball mounts is adjustability, but on the downside it will transfer more load and road irregularities to chassis. Uniball is great for a track use, but not so great idea for bumpy countryside roads. So I wanted rubber strut mounts that were able to adjust camber. The Solution was OEM BMW upper strut mounts with +/- 0,5 degrees of Camber Correction. These are more sturdy than OEM mounts, and raises your car a bit too. That was only welcomed feature for my E30, described on previous blog post. OEM part number for the rubber mounts is 31 33 1 139 484. Note: These OEM rubber mounts are actually more expensive than Uniball strut mounts.
Actually, I never took my car into any car service for toe adjustment. Instead, I adjusted the toe manually. I set up a string in between pair of Jacks, and aligned them as close as possible to both rear and front wheels. Then measuring the toe was easy task by using a vernier caliper. I put toe to zero. It is a good compromise in between cornering and high speed stability. Using a string is quite simple method, and surprisingly accurate. Don’t laugh. They use this same trick for WRC cars too.
Take home points:
- Looking cool is not equal to going faster.
- Do not add too much negative camber for street use, it will only make your car unpredictable and dangerous.
- Adjusting toe is surprisingly easy at home garage with pair of jacks, a string and a vernier caliper.
- Choose upper strut mounts based on the usage. Rubber mounts can be better for street use, uniballs for track. Choose wisely.