Originally Posted by
1QwkSport2.5r
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.
Actually it is not done inside the sleeve !
The results are actually quite good as not only dos it reduce breakin time but it also trues the piston which is often not perfectly round....What we end up with a lower friction piston that makes a better overall seal....Just lapping the piston alone makes a measurable increase in power over a traditionally broken in engine !!! In fact a few of the factory tuned engines feature fitted pistons ..