This page contains links to information and tools that may be useful to model engineers building and designing their own, or other designs. The usual dire warnings apply in relation to the fact that the author is not a trained mechanical engineer and the advice may be worth no more than what you paid for it. That said, anything presented here has worked for me in one way or another—but there are lots of variables involved, so that's no endorsement that anything here will work for you too. In any case, I hereby disclaim any responsibility for negative outcomes!
Front Rotary Valve (FRV)
Rear Rotary Valve (RRV)
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