454Mercruiser Intake question
12-27-2011 | 10:08 PM
#11
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From: Vancouver BC
They didn't come from GM like that, but lots came from Merc. I think it's when they started using the truck long block but weren't using the MPI truck intake. Must've had lots of the square port intakes in stock. Lol.
12-27-2011 | 10:10 PM
#12
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From: Taunton Ma
I would be willing to bet someone got their hands on the aluminum high rise intake and weber/carter carb and thought that they were making a performance upgrade.
They probably figured that was the difference between the 7.4 Bravo and 454 Mag.
I know it is a little different but just as an example I do tons of work and sales with outboards and you wouldn't believe how many people think that they just slap the carb from a larger model on their motor and it becomes that hp!! I see it and hear it all the time!
Or they repowered with a cheaper long block and didn' t realize that the intake/fuel system was different. See that alot too!
They probably figured that was the difference between the 7.4 Bravo and 454 Mag.
I know it is a little different but just as an example I do tons of work and sales with outboards and you wouldn't believe how many people think that they just slap the carb from a larger model on their motor and it becomes that hp!! I see it and hear it all the time!
Or they repowered with a cheaper long block and didn' t realize that the intake/fuel system was different. See that alot too!
12-27-2011 | 10:37 PM
#13
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From: Dover DE
That combo worked better with the carter carb. The only intake they had with the small port was the cast iron junk that did not work well with the adapter and the carter. It filled the gap until the gen 6 efi
12-27-2011 | 11:26 PM
#14
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From: yorkville,il
12-28-2011 | 06:26 AM
#15
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From: Fredericksburg, Va
no, I think they just wanted to have one intake to use on a few different engines..they used that intake on a bunch..thats why they were done for holley & Q-jet's 1st one I saw I said no way came that way...then ran into a few more, some I knew were never apart...nobody said merc never did dumb stuff...
12-28-2011 | 08:00 AM
#16
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From: Chester,Ct
Nothing surprises me anymore, after working for G.M. for about 25 years and having my transmission shop, most of these company's are just about the profit margin and using what they have hanging around.
12-28-2011 | 08:17 AM
#17
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From: Chicago, IL; Onekama, MI
Exactly! A freind of mine was a quality control manager at GM from the 70-90's and he said you NEVER stopped the line for any reason! You were told to do what ever was needed to keep the line running! Looks like Merc had the same attiitude! I have to say that is shocking, especially considering what Merc charges for an engine!
12-28-2011 | 09:11 PM
#18
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From the August '93 PowerBoat:
The Bravo Three uses a Performance Tuned V-8 that can be bought only with this drive as a system. The 7.4 PT's high rise mag intake, tweaked 4 bbl carb, and timing adjustments are designed to improve torque in the critical midrange.
12-29-2011 | 05:25 AM
#19
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From: Chester,Ct
I can see where they would need to play around with the carb and advance as this combo must have leaned out the @@@@ on the motor, funny because the motor actually has a burned valve in it!!!!!!!!!
I know I'm fairly new to the whole boat engine thing but a drag motor would never survive with that combo,let alone have any kind of performance.
I know I'm fairly new to the whole boat engine thing but a drag motor would never survive with that combo,let alone have any kind of performance.
12-29-2011 | 05:57 AM
#20
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From: South Coast, UK
Merc built them this way on purpose on the early Bravo III engines - called it the Performance Tuned engine. Had the Mag intake on small oval heads, different carb calibration and a recurved distrubutor. Supposedly increased mid range torque for cruisers, etc that used the BIII. I have one in my PQ.
From the August '93 PowerBoat:
From the August '93 PowerBoat:
