Originally Posted by jmichaelre
I'm building a fresh 350 and should be done in about a week as long as my parts arrive. As far as the breakin I was going to break in the cam based on the instructions by edelbrock, but they didnt specify anything about engine oil during breakin. As far as the rings go, I have moly faced rings and the college I had machine it for me knew that I was using these rings and told me that they would put a fine plateau finish on the cylinders and said that they should seat during cam breakin or very shortly after. Everyone, I have talked to said to use straight 30 until the rings seat, but Im worried that since its so thick and I need this engine in the truck in the next month that temps will be around 40 degrees and I dont want to starve the cam of oil.
Straight 30 wt. non detergent oil is fine. Add a zinc additive for the initial break-in run if you have flat tappet lifters. If you are running rollers the additive is not required nor is the 20 minute break-in period.
The twenty minute break-in run should be done by starting the engine and bringing the RPM up to around 2000 right away. Idling the engine before the break-in run is completed can be detrimental
. Vary the RPM from 2000-2500 every five minutes or so. Do not try to adjust the carb yet. Do check for leaks and shut down to fix as necessary. Watch the engine temperature and oil pressure. Check the total mechanical timing with the vacuum advance disconnected from the vacuum cannister and plugged at an RPM between 2500-3000. Set it between 32-38 degrees BTDC. This will prevent you from having the ignition retarded and causing your engine to run hot. An indication of retarded timing is if you see the exhaust pipes close to the exhaust manifolds getting cherry red, your timing is most likely retarded or you have a MAJOR vacuum leak causing you to run very lean.
Change the oil and the filter immediately after the twenty minute break-in. Change them again after the first 50, 100, 500 miles. After that, change the oil and filter after about 3000 miles. Do not use synthetic oil until you have around 2000 miles on the engine. Changing the filter is more important than changing the oil. Use a good filter. I suggest a NAPA (made for NAPA by WIX) or WIX oil filters.
The cam gets lubricated by 'splash'. This is why the engine RPM's are well above idle during the break-in run.
the run is completed and the oil and filter have been changed; you can restart the engine and proceed with setting the timing and then adjusting the carb.