No disrepect meant to Grayracer but every engine builder I know (including myself) seats the rings in the cylinder dry. If you are not confident in doing it that way then at least use non synthetic oil for break in. See, this always happens. No disrespect to you, either, but I haven't built an engine dry in, ever, which covers from 1964 to the present, and I'm not about to start. My son's '06 leak tested at a 97% seal 10 minutes after it was started. As far as break in on synthetics, you should probably tell Chevrolet, Mercedes, Porsche, Cadillac, and others that this is a bad idea. They'll void the warranty on some of their stuff if it doesn't run on the specified synthetic for the entire term. Break in is a critical time in an engine's life, and lubrication is more important during this time, not less. Both these discussions have already been had several times, and I'd rather it didn't side track yet another thread.