I don't recall the exact numbers, but the last 250 I built got 307 pistons, AND a .050" head mill, and it still runs on regular gas, with a stock cam, and doesn't detonate. I figure that's about the ragged edge of too much, though!
Jerry

Edit: The 250 rod length is WAY different than a V-8, so you'll need to use the 6-cylinder rods, not the smallblock V-8's.
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!
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