building 273..or not

The 273 is fun because it can spin faster. Also should give better mpg for a regular driver. It has other advantages in the adjustable rockers and forged crank. Indeed, people use those parts to upgrade later small blocks.

If you just care about time slips at the drag strip, you would go bigger, but then you go BB and change the entire drive-train, including rear end. Even for a 360 SB, you probably need to upgrade or rebuild the transmission and a bigger rear-end. Even for strictly drag racing, there is more pride in winning with a 273 or even a slant six.