This engine has several hundred flights on it and the bearings need changing. On disassembly, the cam lobes also seem rough, not smooth and the backplate appears to have been scuffed on one side by the conrod which also has some scratches on the side of the bronze bushing. I have been using Powermaster 20% nitro/20%oil. Is this a mistake with too much nitro? When I reassemble the engine, what is the cam timing procedure?

If I decide to replace the engine, will the 160 twin mount be anywhere near the same bolt pattern?

Thanks for the help.

Rockythe enging