Just how quick were the 273 Commando's in the Quarter-Mile.

Yeah, if you check the chart, the 2bbl,single exhaust,low compression teener, was factored at 170 hp(.53hp/cid). If you built it to 273-4bbl specswhich made .76 hp/cid, then your teener would be around 240hp. That's an easy 30hp over the 210 factored 273. That, from 45 extra cubes. ,EDIT That is to say; build the teener to .76hp/cid. The .76 hp/cid is a pretty easy target to hit. It makes a 340/258hp; and a 360/274hp: easy/peasy.Course that's all theory.
Notice that the 340/258hp engine is pretty close to the 264 hp required to go 12.7 in that 2900 lb A.One might surmise that you could actually detune the stock 340/275hp engine, or the chassis.
Or, alternatively, a 360/274 hp engine could do the trick with a lessor suspension. But then, we already know that 360s get into 12s, with modest suspensions, or heavier As.