I have a 74, 225 here on a stand that I am slowly putting together as time allows, and even after a 30-thou deck shave, my pistons are STILL at 180 thou in the hole. I'm not really happy about that. It has 20-over silv o lite stock style replacement pistons in it on a set of NOS OEM Mopar rods I found via a guy over at the /6 forum.
I started with a head a block and a crank. Didn't get Pistons or rods with it when I got it or I'd have measured how deep in the hole the originals were.
So if I hadn't asked for that deck shave they would have ended up .210in the hole. Really ridiculous huh?
One of the magazine articles I read on the /6 had a fresh engine with Pistons at .210 in the hole. I think it was an article about the red 67 dart at the college in PA. There have been a few written about that one.
I've heard it said that replacement piston makers make the compression height less to compensate for the (slight) potential CR increase from boring out a cylinder. Which might be/ but is even made more ridiculous when you consider that when actually measured out/"blueprinted" as they come from the factory they aren't anywhere near advertised compression ratio to begin with due to all the tolerances of an assembly line.
