Just read something that flipped my view on engine break-in periods

I always followed the old 'baby it for 500 miles' rule, but a technical paper from the Engine Research Center showed modern machining tolerances make that mostly unnecessary. Found it while looking up specs for a new crate motor install. Anyone have real-world experience with this on newer engines?

2 comments

2 Comments

hall.nina4d ago

Wait, they said machining tolerances make it unnecessary? That's the part that gets me. The tolerances are tighter, sure, but what about the initial wear-in of the piston rings against the cylinder walls? That still has to happen. Just slapping in a new motor and going full throttle seems like a huge gamble.

lisaf384d ago

Modern machining is just that good now. The surfaces are prepped to mate almost perfectly from the factory. That old-school wear-in period was for older, less precise manufacturing. Running it hard from the start can actually help seat things properly under real pressure. The gamble is sticking to outdated advice and never letting the engine work as designed.