Breaking in a new engine requires heightened focus, along with some parameters for the first few hours of flight: Stay below 5,500 MSL to assure the engine can run at 65% power or better. Only conduct cross-country flights of an hour or more in duration. Full stop landings. No touch-n-go pattern work. No stalls and recoveries. Limit use of idle power to start up, taxi, and landing. And of course, use mineral oil exclusively for this break-in period.
Source: general aviationSomething old, something new-ish