[Excaliber]

An interesting question has been raised here:

Do you STILL need additional ZDDP after the breakin? I never have seen a definitive answer to that. I assume you do and thats why I run a can of STP myself.

RPM in the magical range is nothing more than 'splash' feeding the lifters and cam lobes. As we KNOW a cam can die within minutes of first being 'fired up' it would follow the bulk of the 'breakin' period is also within 'minutes' of the first fire up. Personally I think it has as much to do with lifter rotation as anything else. This might explain the cam survival when the crank bearings failed. Crank bearings don't 'break in' per se, they need lubrication and plenty of it ALL the time. You might get lucky with a cam/lifter setup starving for a short period.