I have been running this motor for at least 8 years with oil pump harmonics. Sound like a hum in the motor, but only at low speeds(or cam gear), but you feel the viabrations through the oil line. I have drilled the block for full flow ( 90% full flow) oil filtration and run 1/2" hose to the filter and the return. I don't think it is hurting anything, but it is annoying. Oil pressure runs 60psi at cruise and 45 at idle hot. I run 15/50 Mobil 1 for the high zink content. Hope I gave all the info.
The Jalopy Journal
