Originally posted by 4onthefloor
cranking compression PSI is 185
I'm not familiar with the Crane cam you're using but if it is designed for low RPM torque and your static compression ratio is around 10 or 11-1 that could possibly be your problem. The "torque" cams are designed to be more volumetric efficient in the lower RPM ranges and generally work best with static compression ratios ranging from 8.5 to 9.2-1.

You might try dumping some racing gas in it and see if it quiets down. If it doesn't you should probably look for a mechanical cause.