Also, as for which solenoid valves are legal, refer to R78. Finding air flow specifications for some of the valves is a challenge.
Code:
R78 The only pneumatic system items permitted on 2013 FRC
ROBOTS include the items listed below.
...
C. Solenoid valves with a maximum 1/8 in. NPT port diameter, and
a maximum Cv of 0.32,
D. Solenoid valves that are rated for a maximum working pressure
that is less than 125 psi rating mandated above are permitted, however
if employed, an additional pressure relief valve must be added to the
low pressure side of the main regulator. The additional relief valve must
be set to a lower pressure than the maximum pressure rating for the
solenoid valve