Hey all new to the site looking for some insite.. Have a 87 fountain with 370hp 454s. Looking to rebuild and make a little more power. That being said seem to be stock other than the flow through water circulator housing.. And also noticed it has roller rockers. Wasn't the roller rocker arms the 420hp package..? Any info on rebuilding upgrades and hp range I should be safe with the 454 blocks internals etc.. Thanks in advance Jacob ..

The 370 from what I have read it has forged crank, pistons and rods. Rectangular port heads with an aluminum high rise intake and roller rockers. 8.8:1 compression. Great base engine.

A little head work a larger carb and cam change should get you in the 420 range. I'm sure there are a few guys who will chime in with some good combinations.

how fast does the boat go now?have you checked top speed with a RADARR gun.