This guy seems a straight shooter. He works at Westech performance who is the go to dyno place for the Hot Rod and Car mags of the past. He took his smog 360 and bolted on some decent parts and got over 460hp. Mild cam mind you and mild ported iron LA heads. Im questioning the
"Happiness" of his dyno because Nicks Garage just dynoed a 383 originally built to 335hp specs but with a big cam, M1 single plane and expensive Holly carb and did not make this power. In the 90s a legit mopar mag had a 375 hp 440 magnum where they added headers, 509 cam, single plane intake and Holley carb and they achieved 425 hp on their dyno. Just seems if it were so easy to build this power he got with simple parts and smogger pistons there would be no need to purchase zero deck pistons, aftermarket heads and such. BluePrint Engines offers a 408 stroker iron headed 360 that doesnt make this HP level. Im wondering if theres some of that 90s magazine embellishment going on in the modern video clip world here.

https://www.youtube.com/watch?v=Gf2CAPiFJgg