I've been working with one of these and you should be able to hit the rpm your looking at. I've got a 14-8 on mine (its what I had on hand) and get around 7300 with stock ignition. Muffler has baffle removed with a 2'' x .5 diameter discharge extension welded on. I'm still fighting either an air leak or my carb is too big. To get high mixture close my needle is about to fall out running with about 1/4 choke. Adapter was made from stock square drive drilled and tapped with a large diameter washer welded on for prop.

I don't think mine is going work out for my project though. Was going to put it on a bridi old timer but I don't think its going to have the umph needed.

Dave