Sure Red, these are 9ah, they came from some 110 back-up system for computers, I think that in order to keep the batteries at full charge, the rpm of the gas engine will need to be higher during cruise. But I like the low noise level (comparitively) the way I am doing it.
And Thine,the more muffling- the better, and the longer the whole system- the better. My first muffler is a self- built glass lined deal that is not straight thru, and the little 3 1/2 hp Briggs on the end does help a little.
There is very little noise coming from the exhaust. I do hear engine clatter, typical of a air cooled 4 stroke.
Yeah, Denny, it really was a lot of work- kind of a pioneering effort like you did.
Thanks for the comments guys!