What’s your guesses on horse power?

My guesstimating formula

Torque is the easiest to guess most street to mild street strip are gonna be 1.15-1.25 lbs-ft.

So minimum of 1.15 x 365 cid is 420 lbs-ft, The trick is guessing where peak power is gonna occur, I’d say 5500 for your combo depending how well ported the heads. Torque at peak hp is usually down 10% ish.

So 378 lbs-ft.

378 x 5500 / 5252 = 396 hp.

So minimum 396 hp @ 5500 and 420 lbs-ft @ 4000 to max 429 hp @ 5500 and 456 lbs-ft @ 4000.