By making an engine lighter the performance is effectively increased simply because the weight being pulled by the engine is less. That's like taking 1/2 of a pound out of a 50cc powered 17.5 lb. plane. By reducing the total weight to 17 pounds the plane flys better with the same engine. Adding a pipe takes it even further.

Krayzc,

Likely you have a bearing that gave up. It was common in Brison engines that had suffered a few prop strikes over time. Which was the reason Gary always suggested sending an engine in after a prop strike. I had one let go in one of mine after numerous prop hits in a GP 1/3 Pitts. It was an easy fix. Worst case is the crank sections separated and RC Ignition can fix that. If not I have a pair of 3.2's and I'd let you have a shot at one of them. No prop strikes on either