Well I got the engine started this weekend. It runs like a top! Using the stock muffler, I was getting close to 7k with the APC 18X8W prop. With a new muffler and break in proccess, this engine is going to be awesome. Even being new and stock muffler, I had it at full throttle, and with my 13.5 lb lanier ultimate pitts, there is MORE than a 1:1 thrust / weight ratio! For everyone that is wondering if the G38 is a good fit for this engine, I will tell you that it's a GREAT match to the plane.

Thanks everyone for your advice. I should maiden the plane this comming weekend. Pics and maybe video to come!