Just trying to get a comparison between an otherwise identically equipped 420TRS vs 454MAG Bravo boat. I know the MAG is 365pshp and the Bravo eats up around 10%? So that would put crank HP somewhere around 405-425 on the motor itself. So a 420TRS assuming 15% puts it around 360pshp. "Theoretically"....the 420TRS wouldn't have anything over the 454MAG right?

Oh, and if I want ~415pshp out of the 454MAG I need to make over 460hp at the crank, with the exhaust I'll use in the boat. So there's the goal = 454/460hp with wet exhaust.

i looked at the spec's in my 400-460 cyclone manual and i believe it is hp at the crank. i'm not sure how the 454 mag was rated, i'd assume it would crankshaft hp but i could be wrong. the i do like haveing the trs cause of the tranny's even though they rob 10-15 hp. i alway's thought you lose 10% for every 90 deg. change in direction. 2 90's =20% in a typ. io

Thanks. I know the 454MAG is 365pshp but it sure gets fuzzy in these years '86-91. I know the current rule of thumb is black motors=pshp, blue motors = crank HP.

I believe it is the other way around, black motors @ the crank, blue motors @ the prop.