I don't understand why you would want to lap a Ringless aluminum piston to a brass liner that's gonna expand when hot. On paper it sounds nice for a quick break-in, but it also sounds like it takes life off the P/L set at the same time. I can understand doing this with the old Meehanite piston in a steel liner type of construction - those types of engines took gallons to break-in. But an ABC? I'd never allow that kind of thing in my engines. No offense.

On the flip - I'm glad I grabbed an extra piston/liner for my P3. I don't mind long break-ins and tight engines. Tight engines to me mean I'm getting my money's worth out of it.