Originally Posted by Aseras
really really, this is in the factory manual somewhere
The engine from the factory will check out with about 360-475psi of compression pressure
It will take at least 60,000 miles to reach the peak pressure of >550psi.
For the most part once you get to 10,000 miles your compression will be around 510psi meaning that most of the break in has occurred.
Impressive. I'm not sure it's still "break in" at that point per se, but I see what you're saying. The page I was reading explains it's because of the ultra brutal plasma rings or whatever they use in extreme duty engines.....
That and the low RPM limit takes a while to seat everything I guess.