How to get 400 hp out of 1971 340 .30 over

125+hp from bolt-ons? The 340 must have been poorly designed or seriously under rated.
LOL, well, the cylinder heads being as they were for the day did t flow very well and the intake was OK and just fine for the daily driver duties it was designed to do but, WOW! Imagine what a LD-340 on top would have done with a better head.

Alas….. the factory has to do things on the cheap and what’s on hand. Bummer huh?!?!