On a blown alchy deal, I would use a Dart 360 race series head. With some minor porting, they will out pace the CNC 355, and cost less. The reason being, is, that the Race series heads, are a bunch beefier, and thicker, in the right places, and, they work.
I wouldn;t loose sleep about worrying about flow numbers either. I recently did a pair of 557 tall deck, marine 8-71 carbed blower engines, super chiller under blower intercoolers, twin King demon RS carbs, dry sumps etc, on pump gas, that made 1040 at only 5 lbs of boost, and 1300 at 15 lbs. This was with Dart Race series 308's, that I ported. We did use 100 octane low lead aviation fuel for the higher boost levels, but, there was still power left in it, could have easily upped the boost more, and, the heads were small, like 320cc, and barely flowed 380. These 2 engines, went in a 42 foot, MTI Cat, that goes over 140mph. This isn;t a race boat either, but a fully optioned "pleasure" boat.
Frank
Advanced performance
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