I did that with a BTE Flyin King, I had removed a Fox 74 Diesel conversion bur didn't change the clunk line. The glow fuel hardened it up and it was sticking straight out in the center of the tank like a donkey dick. When the tank was half empty the Saito 80 went lean and kicked the Harry Higley Heavy Hub and the prop off. It then went tail heavy and sailed through the dead snag of a pine tree backwards with no sign of wings or tail feathers on it when it came out the other side. The engine and radio equipment survived. At 15.5 to 1 I don't think I'll increase that old 80's compression.