Double-Wishbone Front Suspension Conversion

Fitting 300mm-wide front slicks under an E36 while keeping usable steering angle, scrub radius, roll center, camber, and caster meant the factory strut front end couldn't survive intact — the entire front suspension was re-engineered from scratch.

The wheel was pushed 40mm further forward to open up chassis clearance at full lock and clean up airflow around the back of the tire. A custom upright, front arms, and subframe were designed to be built from laser-cut steel and tube, sized around a BMW E90 front wheel bearing, Porsche 18Z Cayenne calipers, and an 18-inch 13J centerlock wheel. Using the E90 bearing also opened the door to running the E90 M3's Teves Mk60E5 ABS system.

Every hardpoint was placed with a target in mind, not just packaged to fit: bump steer was held to 0.03 degrees of variance across the full 70mm of wheel travel, the camber curve was tuned against real tire data to balance camber gain through both steering and bump/rebound, and the roll center was set to roughly 70mm above ground to control body roll without letting jacking forces get out of hand. Kinematics were validated in ADAMS multibody simulation before anything was cut.

The end result is a front end where camber, camber curve, caster, roll center, dive, and ride height can all be adjusted independently of damper travel — a suspension that can be re-tuned as tires, tracks, or aero packages change, not a fixed-geometry kit.