The arms(front and rear) should be parallel to the ground to give equal up and down travel when the car is loaded. Increase the ground clearance will make the car bouncy as you a compressing the spring further to raise the ride height. As well as increasing the ability to roll over by raising the c.g.
The limiters are there to limit the down travel of the suspension when the unloaded side (inside wheels)of the car in a corner allows to much down travel. the transfer of weight from the unloaded side of the car to the loaded side (outside wheels) may become so great it causes the car to roll over in the corners.
When the car jump the suspension fully extended then compresses on impact so raising the ride height won't improve landings
If the car is bottoming out in the jumps then the spring oil piston combination may be causing the damping to be too soft by the pack the resistance of the oil flowing through the hole in the piston being to low). Usually cured quickly with thicker oil but best cured by changing the piston hole sizes and increasing the shock rebound ( how far the piston decompress after been compressed fully.) changing the piston rather than the oil is better as the spring oil combination may be spot on for the corners and little ruts and bumps, but increasing the rate of the spring or oil viscosity will cause it to bounce over these imperfections. The pack is more to do with the how fast and how much force the pistion moves through the oil. This effect tend to only be noticable at high velocity and and high force. Usually on hard landings. it works by the oil not being able to go through the hole fast enough so in stead of the oil passing through the piston it compresses and become pressurised. due to the presure diffrence between the top and bottom of the piston the pressurised oil at the top of the piston pushes the piston back. (it to do with laminar flow through a pipe and thermodynamics you need to read up on it to understand it fully)
Even though i can't build my shocks properly I think this information is correct.
