Originally Posted by BIG CHEVY 3600
I will be starting mine someday and have been worrying about break-in on the engine. I have read how you should run the engine down the highway at certain speeds and all the other detail things needed to do to properly break in the engine.
I have planed on driving mine to the muffler shop and don't think I can get it on the highway at speeds before getting the exhaust installed. What's the facts on this break-in? headscratch

Most newly built engines do well with an initial cam break-in. You can do this in your driveway by running the engine at varied RPMs (use the throttle shaft to slowly decreas/increase RPM) for 15-20 minutes while watching oil/temp gauges to guard against low oil pressure and overheating. Be sure to look for leaks and listen for abnormal noises. If you're running cast iron rings this action will also help to properly seat the rings. However if you're running chrome-moly rings, usually ring seating will take a few miles of driving.