[ZInventor]

if you have an air tank between the valve and ram, and a mechanism to release the ram after it has been pressurized, you can get the cam to move quite fast.

I believe team 360 used this in combination with a large spring to launch the trackballs during Overdrive.

also, if you need speed, lower the diameter of your cylinder. it won't be as strong, but it will move much faster. if you add a weight on the end of the cylinder, the momentum will impart significant force.