I’m building a 2.5 225 PM this week that was decked .009” on both banks customer bought this motor from a buddy , I built the motor in 2012 , has .030” top pinned Vertex pistons installed , motor was initially built with 1.25 mm thick head gaskets and ran fine , the port side had some issues that I don’t know what , the original owner didn’t notice the .009” stamped VERY prominently on the side of the block next to the deck , he inadvertently installed a 1.00 mm head gasket popped #2 took out gasket as well as the parent metal around sleeve that will have to have a flanged sleeve installed to repair the issue. I’m going to install a new set of pistons and plan on fly cutting the new pistons BEFORE I have Marles top pin them , I’ve tried to fly cut a set of pistons years ago that was top pinned and wasn’t real successful that tooling cuts the aluminum piston like butter BUT when the tooling contacts the hardened pin sh** hits the fan , just food for thought ... If your in doubt take a piece of soft solder bend a crook and install in a plug hole to reach the squish band area , turn the motor through and slowly allow the piston to crush the solder remove and measure it , my danger distance is less than .044” , anything less created by a cut deck will make me go to a thicker head gasket ...Good luck !
Jay @ JSRE
