Hello, and some Avistar Advice
I'm going to try a new prop this weekend... think I'll grab an 11X4 and check it out.
I'll also move the CG back a hair by adding some weights. Those all sounds like 'cheap' trials.
As for the baffle in the muffler, and enlarging the exhaust outlet... um... I'm kinda new to this whole thing. How hard would that be?