[Halon]

I've always read the best way to break it in, is to break it in with some good solid pulls to get the rings sealed up right. The first few miles are the most important because the crosshatch pattern in the cylinders wears off quick, and that's what acts sort of as a "file" and files the rings so they seal nice and snug. And the reason you need to run it hard is so that there is more pressure in the cylinder, pushing the rings outwards toward the cylinder walls so they can be "filed" better.

I'm no expert builder, but this is what I've noticed is the general consensus as of late when it comes to breaking in freshly built engines. I'm sure someone else has more experience with me. But I know when I get my motor, it's gunna be broken in using that idea!