454 mag

[Jochum]

A friend of mine has a boat with a merc 454 mag. Year 88.
On the side of the engine there is a sticker that says 330 hp.
However some people say, that a 454 mag. never has less than 365 hp.
Anyone know??

[Magicfloat]

The early 454 Mags were 330 HP , the later Mags were 365. Unfortunately Merc has had a long histiry of changing model designations and HP ratings on a regular basis. It almost impossible for the public to keep up with it, I've been a dealer for 35 years and I can't keep up either.Only references I know of are the old factory brochures and I don't save them anymore.

[Too Old]

Someone smarter than me can give you a more specific answer.
But here goes....at some point, Mercury quit advertising the HP at the crank shaft and instead gave you HP at the prop shaft. Thus the old 330 becane a 300 or 310 hp listed motor.
So the old 330's are basically the same as the later 7.4 300 hp package.
Someone feel free to make corrections or fill in the blanks......

[Magicfloat]

Fred, you are correct. The confusion comes in with the early "Magnum" designation. Magnum later became the mean a little more hi-performance moter when the early ones were not.But Merc has messed it up again, the new 496 Mag is the std motor at 375 hp,the 496 Mag HO is the performance version at 425hp. Isn't this fun? Would love to get some of their marketing guys in a room with Travis's bat!

[euby]

i'd say in 88 the the 454mag was indeed 330hp http://free.***boat.net/ubb/smile.gif

[Bigggus]

In 1987 the 454 Mag was the 330hp motor with an Alpha one drive. When Merc introduced the Bravo drive in 1988 the pervious 454 mag became the 7.4 and the new 454 Mag was the 365 hp. version.
Kurt.

[Too Old]

Man, I need a score card to keep up. No onder there's so much comfusion about mags/vs/non-mags. You sure couldn't tell which ones had the good components simply by the hp ratings. At least I couldn't.

[GaryC]

Now too really make you and me more confused, my 1986 Donzi Z-25 had a 454 330 non mag hooked to a TRS drive. It was called a 330 TRS.

[fwk]

With TRS drives you could get the 330, 370, 400 and the 440 There was a 420 in there also. Forrest

[Too Old]

Forrest, any idea what years the 420 was offered?