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

Not a commando, but I watched a '67 barracuda with a 273 2bbl, auto, single exhaust that was just about as original as you will find. It ran 17.30's. I have no idea what the gears were.
As for me, I've owned 273, and only the 2bbl's. I have never taken one to the strip.

My totally stock (exc electronic ignition) 273 2 barrel 65 Signet ran a 17.00 with 2.76 gears- in late 80s at 75/80 near Frederick MD