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snowman
04-30-2004, 03:00 PM
Can any one help me with the differnce between 496mag 375 hp and 496ho 425 hp? I was told they booth have cast pistons and cranks. Are the compression ratios the same cam and cylinder heads differnt ? Also fuel systems any better on ho ? Thanks for any info!

Barry Phillips
05-02-2004, 09:39 AM
I have a 375 hp 496 Mag and I have pondered the differences also. The specs seem identical except the HO uses a stainless steel cam and is rated to run from 5000 to 5200 rpm where the 375 is rated to run 4800 rpm, yet my boat is set up to run 5,000 rpm from Donzi with a 23 Mirage Plus. I am willing to guess that Mercruiser found the 50 hp with a slightly more agressive cam profile or in the CPU. Although I have been told that both cams have the same profile and the stainless was used for durability.

olredalert
05-02-2004, 10:08 AM
-------Big difference in price, I think............Bill S

gcarter
05-02-2004, 10:35 AM
Yeah Barry, I bet your right. 200 to 400 rpm could easily get you another 50 HP! :smash:

George

customan
05-02-2004, 03:52 PM
I have the ho , I was told its the computer, it controls ignition curve ,fuel,ext. just wait someone will come out with a chip and pow u got an ho performing motor for much less than $5500 upgrade but when they make one for the mag they will make one for the ho! cant wait!!!! by by

cigarette30
05-02-2004, 09:39 PM
There is a few other upgrades, but also the H.O. has the better outdrive .... I stand corrected if this is not true

RickSE
05-03-2004, 11:19 AM
Cig is correct.
496 MAG-HO comes with Bravo-1X
496 MMAG comes with Bravo-1

GM Powertrain Marine Engine Specs (http://www.gm.com/automotive/gmpowertrain/engines/vortec/apps/marine/index.htm)