11-25-2025, 05:52 PM

65madgoat

Chief Ponti-yacker

Join Date: Feb 2019

Location: USA

Posts: 804

Ok photos of GM pistons attached. I am no engine assembler, but just mic'ing them I get about 4.156 or so at the skirt and 4.078 at top.

Stock 455 block with these oem pistons had a 10 over bore so around 4.161 or so if I recall.

Does this add up?

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