This is how i break in an engine.

1. initial startup....let run for 30min, dial in the A/F, checking for leaks, etc. , shut off. Use only non-detergent oil during break-in.

2. street tune with the following method to seat the rings: 2nd or 3rd gear, accel half throttle from 2500 to 6500, let off gas completely as to create heavy vacuum. Do this 5-10 times. Dial in the A/F during this time. Change oil and filter.

3. Heavy full throttle street tune/dyno time.

I have built probably 20 engines for people this way.