273 build idea......

I would run it as is, but that being said, a engine with small bores is harder to get compression in. The factory commandos had dome pistons to reach a advertised 10.5 to one, as a comparison, a 340 can be 10.5 with a flattop. A zero deck 273 will have a lower compression ratio than say a 408 with zero deck. So the thing to do with the 273, is try to find (or have made) $$$$ a true flattop, thin gasket, and run small chamber heads.. But like I said, I would run it as it is... 2 cnts