Detonation is related to either timing or compression/octane issues. I would double check the timing. Did you degree the camshaft? I think some cam gears are designed to allow some retard or advance at installation. If the compression is too high, and your using low octane fuel, detonation (knocking) will occur as well. 18436572, Good luck. A call into the builder would be my next step.Crate motor fully blueprinted, new carb Holley 600 cfm. The engine knocks under acceleration. Sounds like a diesel motor. Timing is all correct. We've tried taking some timing out and putting extra timing in and the motor still knocks. Does anyone have an idea of what the issue could be?! I know this is a general question and I don't have much info on it. I am posting this for my father who does not visit sites like this. Thanks in advance for any replies!!