The maximum pressure for a Vex pneumatic piston is 100 psi. For a Pneumatic tank it is 250 psi. My question is would it be safe to pump up a pneumatic tank to more than 100 psi and then use a pressure regulator (which is included in both pneumatic kits) to limit the pressure leaving the tank to 100 psi. This could significantly increase the number of strokes you could get before exhausting the tank.
Also, if this would work, would it be competition legal?
100 psi is the maximum safe system pressure for the VEX pneumatics. As such charging the tanks to any pressure greater than 100 psi would not be competition legal or recommended for non competition use.