Naturally Aspirated, not against a /6 build but what's the cfm you can get of a /6 head?
It's got to flow 33% better than a v8 to have same power capability, then you got rpm.
A stock 273 head has way more NA potential then a ported /6 not knocking if the OP is ok with that, all the power to him, be keel to see another built 6 as long he knows what he's up against.
