That's too bad on the shape of that 273. I have wondered about 273 Commando in a stock class drag race build. And what nicer than an A-body '67 Barracuda? It certainly has some advantages in the small cube arena. Higher compression, solid lift cam and tight heads with a small stock 4 barrel? If built right, to NHRA specs, it could certainly surprise a Stock class.
Im guessing somewhere in the "K" class range? (Though that may be by year.)
I'm just thinking, I bet it would be throttle quick and very consistent. Which is what class racing is all about.