Rebuilt 360 4-speed in a 73 dart sport. Motor had a good break-in with brad penn break-in oil left in for first 500 miles per builders suggestion.Switched to shell rotella after first change of oil. After about 800 total miles motor started ticking on cold startup after sitting for a few days. Lasts for say 3-5 minutes, exhaust note sounds odd and runs a little rough. sound goes away and motor smooths out.Runs fine after that, yet always has the same symptoms after sitting for say 5-6 hours.no overheating missing or other symptoms
Could it be a lifter gone bad and bleeding down? I pulled the valve covers and did not notice anything obvious a miss, no bent pushrods or rocker adjustments let go. Has comp cams pro magnum adjustable rockers. Thinking of pulling the intake and inspecting lifter and cam to eliminate fear of wiped cam lobe.