1974 360 horsepower rating
dan, i'm *assuming* you've seen this:
https://gmauthority.com/blog/2022/1...974-plymouth-duster-360-in-a-drag-race-video/
in the article they give the weight of the duster and if you run the ET/MPH/weight thru a drag calculator that maths out to 260 net horse
on back to back to back runs he averaged low 14's with a 13.8 at 99 break out.
so i'd say somebody who really knows their nuts and bolts could probably tune themselves to possibly 300 plus and probably mid 12's with some chassis work.