I am not a professional, but I have the use of an excellent professional machinist, who is also about my best friend. We have done five or six benzes together, mostly with his work, and usually we have reused the pistons. He measures the wear on the ring lands and so forth and makes a determination of condition. When I had pistons that were too worn we went through all the spares I had and found good enough used ones to reuse.

Usually we have done the sleeves and rebored them to match the diameter of the used pistons for factory new clearances.

Tom W

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.