The SCTA rules separate 302 (pre-1956) from 292 (post) because the power potential difference is large.
The Ford 300 leads the pack (which includes AMC 258) in max power, speed equipment is available.
I'd like to see one of the bigger Japanese L6 engines converted to distributor and carburetor. Even the little (183") Toyota 2JZ is 225 hp in stock form. The 273" FZ is cheap in JY, the Nissan TB is 290".
I know, the V6s are hotter, but they look wrong (to me) and sound terrible!