There is a lot to learn about these cars, but there is a ton of information if you know where to look. For those that don't know, a car like this is built off the suspension design from a Volkswagen bug. The chassis in my rail literally has the frame horns from a bug built in to locate the transaxle and trailing arm pivots. A lot of the technical information I've researched has come from Volkswagen sources.
The front and rear suspension are a trailing arm design, and although limited, they are quite capable. Compared to a stock bug or Class 11 car, the suspension components on my rail are "upgraded". In the front the beam is 10 inches wider (the two parallel tubes, not whoop scissors), and the trailing arms are 2 1/2" longer and uses coilovers instead of torsion bars. The rear trailing arms are called a 3x3 (3 inches longer and 3 inches wider) and also uses coilovers instead of torsion bars.
The front end doesn't have a ton of travel, but it is so light it skips over the top of bumps. You can pretty much grab the beam and pull the front end off the ground. The front is limited by steering tie rods, trailing arm length, and shock setup. I have an 8" stroke shock now, but its common to use a 10" shock.
The rear end is limited by ground clearance at bump and CV angles. I have a 3 rib bus transaxle with Type 2 CV joints, so a pretty limited setup. The Type 2 CVs get around 17 degrees of angle before they start to bind. The normal upgrade for this is the 930 CV joints with around 25 degrees.
