I had the honors of breaking in my 360 AK4 Lycoming in my Sundowner.

For the first 25 hours, I ran it full throttle and full rich and flew no
higher then 2500 feet. My A&P said what ever I do, don't baby it. Run
it hard and rich for those first 25 hours.

Yep, that's the same procedure we followed with out overhauled O-540 two
years ago.

The engine starts easily, runs great, and burns a quart of oil every 15
hours. It's been absolutely perfect, knock on wood.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"