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#21
07-20-2023, 11:01 AM
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Build looks good aside from dished pistons and 72cc heads. That's a decent amount of "squish" area. SBC's absolutely LOVE a flat top or even domed pistons and "tight" combustion chamber. They also love higher compression and can easily run higher compression ratios on pump gas without issues.
Keep in mind that the very best of the best of the factory SBC offerings (the 327/350hp and 350/350hp) used a domed piston, 64cc heads, a very well designed combustion chamber, good port flow, and tight squish with a .020" steel shim head gasket. With than much dish (10cc), plus 72cc heads that's 82cc. Not a death sentence but you don't have enough "squeeze" in a "383" build for a well designed HR cam with 230/236 @ .050" duration on a 110LSA. That's the root problem and I'd either increase the compression ratio by a full point or put 10 degrees less cam in it, and I'd move it out on a 112LSA instead of 110 to "tame" things down at idle so it works well with "normal" timing and fuel curves........
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