[Mike Martus]

As long as ALL parts are OCCRA legal parts this is ok. What you are doing is allowing both cylinders to move at the same time. This will work as long as both cylinders are the same bore and stroke.... unless you don't care if they move at the same time are are coordinated.

Remember you have X air in reserve and x air being brought in.

Question? ( you do not have to answer ) if you have two cylinders, different bore which one will move first in your setup described? Food for thought!