Bump Steer is the change in wheel direction caused by the tire moving through the suspension movement (cycle) without input from the steering wheel. So, as you hit a bump in the road the tire steers either left or right while the steering wheel remains straight.Your beam car has bump steer. If you have a stock VW steering box you have more Bump Steer in the left front wheel than the right because of the shorter tie rod. This is part of the reason to relocate your steering box to the center of the car. It allows you to divide the Bump Steer between both front wheels thus balancing the steering geometry and handling of the car. Bump steer is an inherent flaw in the the VW beam front suspension design. It can be minimized but not eliminated. It is not a big deal because we all manage to drive our cars from point A to point B without even noticing it. However, we should be aware of it so we can refine the handling of our off-road cars.
Definitions:
Bump Steer- Tire direction change due to suspension movement.
Cycle- Move suspension from top to bottom of suspension limits.
Rack and Mount Installation:
The "How To" is really very simple. The quick answer is "about" 6 degrees forward and centered. You will need to mock it up several times before you lay the final welds to be sure that you are keeping the bump-steer to a minimum through the full range of motion. You'll never get rid of the Bump Steer, but you can minimize it. You should try to keep the Bump Steer to a minimum at ride height by cycling the suspension repeatedly in that range while making small adjustments.A little Bump Steer at full compression is OK with me, I usually brace myself and hold the steering wheel more tightly when I hit things that will fully compress the suspension.
You will need to mock up your suspension without shocks or springs. This means that you will need to remove your torsion springs to cycle the suspension.
Tighten everything, and cycle your suspension, taking measurements in various positions. Use clamps to secure the rack and mounting bracket, and try different angles, without moving form center until you come up with the least possible toe change at ride height. Ride height can vary from one car the next so measure the distance between the upper and lower shock mount before you take the first step. A simple angle finder is good for this layout and assembly.
