We really need concise info on Pneumatic systems.
Search the web.


Nice and simple guide.
http://www.teamdavinci.com/understanding_pneumatics.htm

My own attempt at a simplified guide.
http://www.teamonslaught.fsnet.co.uk/pneumatics.htm

There is a maximum extension speed that your cylinder can reach for a given leverage ratio and mass to be thrown..... based on Acceleration = Force / Mass and Velocity = Sqrt (2 * Acceleration * Distance travelled ).

You should then calculate the flow needed..for filling you cylinder quickly enough... from the maximum extension speed.

http://www.hassockshog.co.uk/flipper_calculator.htm