The 273 heads would need a flow bench so you could Port them and make sure they flow in that 220 CFM range basically get them worked up to a stock 360 head but higher velocity.
It will shut off at 5,ooo rpm with most cams for the app...because of the heads small port volume to stroke.
It will do what you want....make big low end and not rev high.
Engle has a fast rate 204/216 .479 lift 112 or 114
