Fixing the driveability issues, Part 1: Suspension Geometry

When I bought the car, I really loved the sound and responsiveness of the V8 engine. But the handling was plain awful. I spent the first driving season by fixing and optimizing the driveability. The main reason for bad handling was obvious: the suspension was set too low, causing multiple issues in suspension geometry. At times, I was blaming the V8 engine to be too heavy for E30 chassis. This was to be proven wrong hypothesis.

Effects of lowering E30 too much can result into following:

Front:

Increased (static) negative camber,

Control arms in wrong position 1: roll center gets worse,

Control arms in wrong position 2: decreased (dynamic) negative camber while cornering,

Rear:

Fixed semi-trailing arms in the rear axle will increase both negative camber and toe in.

The suspension appeared to be designed for a stance car, although it was high quality components from KW, full Variante 1 kit. All bushings had been changed to Powerflex, thus those were not the problem either. Even on its highest setting the car was too low, resulting into wrong suspension arm geometry. The strut threading allowed you to set the car from low to below the ground. That was ridiculous.

The fix: I had to add custom made raiser plates made of nylon in order to extend the springs.

Custom made raiser plates made of nylon.
KW Variante 1 coilovers with a raiser plate attached to an eccentric upper strut mount. Note the markings in the coil stands for linear race spring (70N/mm), 140 is the height in mm. Helper spring is placed above the main spring. Its only function is to keep the main spring attached, while car is lifted. Helper is 20-60-80, meaning 20N/mm, 60mm inner diameter and 80mm of height. 

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