I have the exact same problem with the 47k SF I dropped in the Custom in Dec. Quiet at start, great performance, 40psi running around but had to drive to Balt twice and rockers and or lifter(s) got loud and acted like eng missing. Shut down and after waiting awhile, quiet again When VT ticking gets loud oil pressure drops to 25-30psi. I'll take VCs off Sat and see what's going on. Thanks Mart
Changed oil 4 times, Liqui-Molly thru twice and added Rislone on way back from Balt...no change. 455 set for 30 years...I primed oil pump with Vasoline before starting, but I'm afraid Johnny didn't when he started it down in Texas. Thanks Mart