[JCharlton]

The Cv value refers to the effective resistance to air passing through. Higher Cv values let air through with less resistance (faster) and FIRST probably limits this for safety reasons, as well as to give a break to teams that can't afford specialty stuff.

You can do things like run two solenoids in parallel to halve the resistance of the valve. Also look at doubling long runs of pneumatic tube, that has a surprisingly high resistance.

Simple test is to pump the cylinder back and forth with your hands with and without the solenoid attached (just attach to the open solenoid port) to see how much it slows down the stroke. Then try with varying lengths of hose.

Good luck!