I couldn't find any either so I wrote an excel program that integrates the forces to get the piston step response. The response is dictated by the valve coefficent of flow Cv or effective area. The effective area of the SMC valve is 4.86mm^2. A valve is either operating in subsonic or sonic conditions. When it is in sonic conditions, the flow rate is limited by the speed of sound. Otherwise , it varies as the square root of the pressure drop across it. It gets a little more complicated because every component in the pneumatic flow chain has its own Cv (area) and the squared Cv's add like resisters in parallel.
You can take a wag at the maximum possible piston speed assuming it is restricted by the speed of sound.
speed_ips = 13500*factor*A_valve/A_piston
where A_valve = 4.86mm^2, A_piston is the area of the bore and factor is a degradation due to the system fittings and piping. factor reduces the effective A_valve. I would use factor of .3 to .5.
So rewriting this in terms of cylinder bore_in we get
speed_ips = 84.76*factor/bore_in^2
Assuming a factor of .5 and a bore of 1 in then the max speed would be about 42 ips. A 2 in bore would be 1/4 that.
The above assumes standard day sea level conditions.
My model shows that the SMC valve is sized well to keep the .75 in bore cylinder in sub sonic flow conditions most of the time. The 1 and 2 inch bores are flow limited unless driving very large loads. So if you want speed, use the smallest bore. If you want kinetic energy, load the piston as much as you can with a weight. This slows the piston down and allows the piston to be work limited (piston force*stroke) rather than speed limited. When work limited, you can typically get an efficiency of about 35% of what the piston could deliver if moving really slow against a heavy weight than when it is pushing a lighter load.
For example, when pushing a 10 lb load at 60psi with a .75 in bore , a 12 in stroke can deliver about 8.6 ft lbs of kinetic energy. The max would be =Bore*Force = 1ft*24lbs=24 ft lbs, so 35% efficiency. A 10 lb load would be typical of a piston pushing a 2lb weight with a 5 to 1 lever arm.
These results are yet to be verified with FRC testing... I have however done some verification with the vex pneumatics while working with a vex catapult. Here are some forum posts if you are interested:
http://www.vexforum.com/showthread.php?t=18391
http://www.vexforum.com/showthread.php?t=19042
http://www.vexforum.com/showthread.php?t=19003
Also a little more in my vex blog:
http://vamfun.wordpress.com/