Gasifier/N.G. generator. Will it work?

I know a 3" restriction is supposedly only good for 25 h.p… I’m going to buy an onan Lp/ng 20kw genset.My question is, being the 4 cyl. ford engine will only be turning the genny at 1800 r.p.m.'s, is there a chance that the 3" restriction will work alright the way it is being it’s only running at 1800r.p.m.'s on a 40 h.p. engine? Those of you that saw my video know i produce alot of gas. Thanks Dan

Morning DannyC
Short answer os yes 3" will work with this engine. Been done. DO NOT GO ANY SMALLER. Depending on your fuel type (pellets, screened chips or chunks) and the sizing of it you may benefit from going larger to 3 1/2 inch.
Longer, specific to this engine answer is in here if you read it all:

Regards
Steve Unruh

Thank you Steve for responding,I’ll give it a go with 3".I read thru some of your link to small engine forum,lots of info…Lots more learning to do,nice to know i can impose on you and others on this site for help.Maybe someday i can contribute. Dan P.S. I did’nt see the picture you posted with your reply, that looks exactly like my s.s. flange restrictor plate. Guess thats why you posted it,had to do a double take when i saw it.(Who wudda thunk!) Dan