Search Rock Auto for Chevy 307 pistons. They're the exact size as a 250 but are flat tops. That's what I have in my 255, 0.040 over 307 pistons (255). They have Sealed Power cast flat tops (which is what I got), #295P (different letters depending on overbore size). Check Summit, Amazon, etc., I ended up getting 6 pistons for $87 incl shipping. It'll make your 250 around 9.5:1 compression.
Last edited by 47Thriftmaster250; 04/01/15 03:49 PM.
