The Stovebolt Site Forums The Shop Area Engine Shop 250 engine build.

I've been reading and doing a little research on building a 250 engine. I've been to some other web sights , and have ordered Leo Santucci's book about the inline engines. Seems everybody talks about putting 307 v8 Flat top pistons in the 250 to up compression,However no one will say what manufacturer, what year, or a part number that they are using. When I look for these pistons, they seem to all have a chamfered top edge, not a flat straight cut top. I'm thinking maybe the early ( 1968-1970) models had a true flat top. Does anyone have a part number and company name brand of piston that is used for this?
Thanks for any input.

I don't have any numbers, but have run into the same thing you have. The big chamfer probably decreases the compression enough that it's not worth the trouble. Try looking at a forged piston, the cast ones all seem to be chamfered.

Thanks for the response Joe, I'll look into it further and maybe look into forged pistons.($$$$). May just wind up rebuilt as a plain old 250.

Perfect Circle # TC-1737. There's a set on Ebay right now, .040" oversize.

https://www.ebay.com/itm/185155177277?

Silv-O-Lite # 1438:

https://www.ebay.com/itm/331741811966?

Even the ones with the chamfer, like Speed-Pro, Sealed Power, and similar ones, give a compression boost over the dish top 250 pistons. Sealed Power and Speed Pro offer hypereutectic alloy, which is much stronger than regular cast piston material, and half the price or less of forged. I've CC checked several sets of both designs. There is a big difference between information that gets repeated on various websites about a rumor "I heard somewhere" and facts presented by someone who has "been there- - - -done that". Guess which category I fit into? I built my first flattop piston 250 in 1985.
Jerry

Thanks for the info Jerry, Will take the block to the machinist this week and have it checked