Bingo if my CR is too high it would explain the detonation possibly but also I don't know what cam is in there. Ultimately I want to try and estimate the CR but I also don't know the swept volume etc so I don't think I can do that.
Ok, so it is detonating? Then those numbers I believe are correct. Dump some 114 octane race gas in it and see how it runs. It's probably a 12.5:1 engine.
