307 Chevy V-8 pistons fit the 250 as a direct swap. They're flattop, while the 250's have a big dish in the piston crown. The head will also take a .050" milling job without getting into piston/valve interference problems. Combine those mods with a somewhat hotter cam, something in the 270 degree duration range, and it makes the 250 come alive.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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