Five Keys To A Good Leaf Spring Suspension (click for video)
by EATON SUSPENSION

1. Use Multi-Leaf Springs

Use multi leaf springs. Multi-leaf springs can be custom made, which would give you the ride quality and the right height you’re looking for. See article on mono leaf springs.

2. Roll and Taper Your Leaf Ends

Make sure the end of the leaves are rolled and tapered. Rolling and tapering the ends reduces hysteresis which results in a nice riding vehicle

3. Never Adjust Your Ride Height With Blocks

Do not use blocks to either raise or lower the vehicle. The use of blocks is the leading cause of handling problems. You want to get that spring seat as close to the centerline of the axle as possible. This greatly reduces axle wind up.

4. Make Sure Your Shackle’s Angled Correctly

You want the shackle to be right around fifteen (15º) degrees from vertical towards the front f the car. An incorrect shackle angle increases the amount of force required to flex the spring, and the more force the harsher the ride.

5. Choose The Right Shock

This not only applies to leaf spring suspended vehicles, but all vehicles. That is choosing the right shocks. Older cars and older car designs were not created to use gas shock absorbers, they were designed to use hydraulic shocks. In fact gas shock absorbers can add up to 75 pounds for the initial force to get that spring to move.

WATCHPOINT: Morgan rear dampening went from André Hartford dampers (a sissor-like friction dampener) to Girling Hydraulic lever arms and then to Armstrong lever arms at the rear. In the 1980s, modern shock absorbers began to be retrofit..(though TOK 258 used a system similar to the popular Rutherford shock conversion for the LeMans win as early as 1963). Gas charged shocks must compress before the oil can be forced through the valve. Accordingly, the chance of a softer, smoother ride is decreased with gas shocks. Traditional Morgans four wheelers to 2019 were designed from the first using hydraulic shocks. They are better off using KONI and AVOs (liquid filled), than KONI and avoiding GAZ, SPAX and BILTSTEIN which are all gas charged. If you are absolutely convinced that gas shocks are best, use low charge gas shocks.

It’s best to choose the shock by application use the best quality non-gas shock you can afford.