350 mag mpi 7.4 efi interchangable?
01-16-2014 | 04:21 PM
#12
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From: Tampa Bay Area Florida/ North Miami Florida
So what Kind of boat is this.. If the 7.4 in question is a 330 hp motor, then your performance may not be any better or as good as the 350 mpi. If its a short boat thats not heavy, the 330 7.4 will just add weight. If its a big heavy boat then the extra torque of the 7.4 will be nice. As far as I know, there are only 2 plugs merc uses. A 10 pin and a 14pin. There is a 10 pin to 14 pin converter available so that wont be a problem. As far as EFI vs carb, the plug is the same for 350 carb or mpi and 7.4 carb or mpi.
Chris
Chris
01-17-2014 | 04:11 AM
#13
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From: westville, NJ
25 cuddy. 4500 lbs. right on the borderline of being underpowered with small block. bravo gimball housing. was a B3. engine gone drive gone. I have a few carb small blocks around. probably gonna run one for the time being.
01-23-2014 | 06:06 AM
#14
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From: Tampa Bay Area Florida/ North Miami Florida
Stroke one of those small blocks you have to a 383 and couple that to B3 drive and that will be the perfect combo for that size/weight boat. I dont think a 7.4 330hp will give you any advantage in that boat..Will just make it heavier. Most mild build 383's are 400hp and equal or more torque than the 7.4 330. A B2 will save you some cash and still do very well.
01-26-2014 | 06:55 AM
#15
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From: westville, NJ
was gonna go B1, but i think a B3 just fell into my lap too cheap to pass up. how much slower is a B3 than a B1? of course, this is not a full throttle boat by any means. this one is for her. still shopping for one for me.
01-30-2014 | 08:14 PM
#17
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A buddy of mine has a 25 Cobalt with a 496Ho & B3, that boat jumps on plane almost instantly & will run low 70s. I have driven a few B3 boats & find they maneuver around the docks better than a B1. IMO if the boat had a B3 on it & you have one I would use it, the 7.4 would work well with it. Randy
01-31-2014 | 11:03 PM
#20
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From: Tampa Bay Area Florida/ North Miami Florida
It would not do 70 with a 525 in it.. The B3 will reach a wall at 60. The amount of power it would take to push a B3 from 60 to 70, would break the drive. I did not say 496HO vs 496 because everyone on here, except you, knows it will not matter if it is a 496 or 496 ho.. or a 525... ITS not going to do 70. Back to the posters questions. The B3 he is wanting to run with a 383 in that boat will do about 50-55 and it will be a great ride..
Chris
Chris
