AL427SBF Al Talk to Neil or George about breakin, for this motor. My list for new break ins is a little different than others,
Normal 10-30W
oil. The motor should have all metal surfaces covered in prelube and or
oil from build up. I remove inner springs and run a set of worn out low pressure springs. They are good for about 3,500 rpms and start to float. IMO the most important thing is getting the rings to breakin with the cylinder walls for good sealing and low leak down numbers. Oiling splash of the lifters and camshaft is next. This is a reason for not letting a new motor run at idle and time. Preoil the motor, drop in the distributor and fire it up. Go right to 2,000 rpms min and stay there for breakin. 15 minutes, turn off. Change
oil and filter and do again with a good 10-30w or 10-40w oil. I would also add a bottle of oil suppliment from Lucas or EOS from GM to the motor. 500 miles or 4-6 hours on the dyno. Change the oil and filter, install the correct valve springs and keep the rpms under 5,000. Would let motor idle for no more than 1 minute and turn off. IMO idling kills solid cam or solid roller motors. After this time goto and oil you want. If you are racing, after every 2 events, new filter and oil changes are done. This is to prevent any motor issues. Cutting open filters, having a magnet drain plug in the oil pan, once a year bottom end check for play and clearance. All this has help me get 6-7 years out of a motor without any major breakage or damage.
Side note and this is an on going thing here, PREOILERS like an accusump, buy one and use it. I have been running one for 8 years and it,IMO has helped save my motors on the track. If you are not going drysump, than this is a cheap investment against your $17K motor for a long life. 2-3 quart. Rick L.