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How to tell a 454 Mag from 7.4 liter

Sorry for the noob question here, but I'm looking at a 1993 Sunsation 25 Aggressor that the owner says has a 454 Magnum with 365 hp. However the engine cover only says 7.4L/Bravo. Don't know if this is significant or not. Is there a way to visually tell the two apart?

My 1993 454mag said "454 Magnum" on the plastic carb cover. If it is the original cover, then I would suspect it is not a magnum engine. The intake manifold is an aluminum high rise on the magnums. The non mags have a flat iron intake.

Quote:

Originally Posted by Griff (Post 2297945)

Griff,

Thanks for the input. The guy has had the boat for 2y but doesn't seem to be too knowledgeable about previous engine work. I see an MSD ignition, Holley 850 carb and a somewhat lumpy idle that would be indicative of a slightly hotter cam than stock. He and the previous owner (found the previous sale ad online still from 2y ago) both claim 70mph + on a Bravo 4-blade prop (unknown pitch).
Were these some common upgrades to that series motor?

My 365hp said Magnum on the cover and also said 365hp listed on the cover.