rebuild time
#11
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Joined: Oct 2013
Posts: 2,888
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From: SF Bay Area
I’d actually argue that a boat puts more of a load on an engine than a dump truck. Does a dump truck need brakes? A boat doesn’t because it’s constantly overcoming enough drag to stop it dead should you cut the throttle.
I also put a supercharger on my 272 Baja, but pulled it off before even running it due to the input I got here. We all go down the same path, lol.
A Bravo 1 can reliably handle about 350hp. Depending on many things such as boat weight/efficiency, prop size, drive depth, and operator self control when hammering the throttles. Some drives live fine with 500hp while others pop with 400hp on glassy water.
Something critical on marine engines is the fuel flow and oil coolers, and it’ll cost you much more if you skimp in these areas. You can expect at least another $1k in rigging there, or you’ll toast that engine in no time
Is the current engine an MPI?
I also put a supercharger on my 272 Baja, but pulled it off before even running it due to the input I got here. We all go down the same path, lol.
A Bravo 1 can reliably handle about 350hp. Depending on many things such as boat weight/efficiency, prop size, drive depth, and operator self control when hammering the throttles. Some drives live fine with 500hp while others pop with 400hp on glassy water.
Something critical on marine engines is the fuel flow and oil coolers, and it’ll cost you much more if you skimp in these areas. You can expect at least another $1k in rigging there, or you’ll toast that engine in no time
Is the current engine an MPI?
#12
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Joined: Jul 2020
Posts: 14
Likes: 1
I’d actually argue that a boat puts more of a load on an engine than a dump truck. Does a dump truck need brakes? A boat doesn’t because it’s constantly overcoming enough drag to stop it dead should you cut the throttle.
I also put a supercharger on my 272 Baja, but pulled it off before even running it due to the input I got here. We all go down the same path, lol.
A Bravo 1 can reliably handle about 350hp. Depending on many things such as boat weight/efficiency, prop size, drive depth, and operator self control when hammering the throttles. Some drives live fine with 500hp while others pop with 400hp on glassy water.
Something critical on marine engines is the fuel flow and oil coolers, and it’ll cost you much more if you skimp in these areas. You can expect at least another $1k in rigging there, or you’ll toast that engine in no time
Is the current engine an MPI?
I also put a supercharger on my 272 Baja, but pulled it off before even running it due to the input I got here. We all go down the same path, lol.
A Bravo 1 can reliably handle about 350hp. Depending on many things such as boat weight/efficiency, prop size, drive depth, and operator self control when hammering the throttles. Some drives live fine with 500hp while others pop with 400hp on glassy water.
Something critical on marine engines is the fuel flow and oil coolers, and it’ll cost you much more if you skimp in these areas. You can expect at least another $1k in rigging there, or you’ll toast that engine in no time
Is the current engine an MPI?
I got the fully machined block for 500. fully bored, new cam bearings pressed in, and boiled i thought it was a good deal i just figured id have to stud it 🤷♂️ i'll probably just leave it N/A since i really don't want to piss away $ so I can try to make it as reliable as possible, and not toast my new outdrive. I'll probably just get headers and an intake for it and call it a day then
#13
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Joined: Oct 2013
Posts: 2,888
Likes: 148
From: SF Bay Area
it was the original 88 gen IV 7.4 not even a mag just the regular one, and no it was carbd it has a quadrajet atm. I just planned on reusing all my accesories, oil pan, oil pump etc. all the mounts and bolt holes are the same on the 2 bolt. i wish i had $ for a new motor and didn't have to guess but im just unbroke enough to afford parts, and bored enough to do all the work myself lol
I got the fully machined block for 500. fully bored, new cam bearings pressed in, and boiled i thought it was a good deal i just figured id have to stud it 🤷♂️ i'll probably just leave it N/A since i really don't want to piss away $ so I can try to make it as reliable as possible, and not toast my new outdrive. I'll probably just get headers and an intake for it and call it a day then
I got the fully machined block for 500. fully bored, new cam bearings pressed in, and boiled i thought it was a good deal i just figured id have to stud it 🤷♂️ i'll probably just leave it N/A since i really don't want to piss away $ so I can try to make it as reliable as possible, and not toast my new outdrive. I'll probably just get headers and an intake for it and call it a day then
There’s a TON of engine recipes here for solid reliable power. Do you have the 088 heads? Boat in fresh water or salt?
#14
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Joined: Jul 2020
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Ill even save you more money as it’s been proven here time and time again that headers gain you zilch until you start getting into the 600hp range, but finding some good aluminum manifolds are a good idea. Headers can be a little delicate with the twin wall construction where the vibration weakens the welds and hydro locks the engine.
There’s a TON of engine recipes here for solid reliable power. Do you have the 088 heads? Boat in fresh water or salt?
There’s a TON of engine recipes here for solid reliable power. Do you have the 088 heads? Boat in fresh water or salt?
the heads looked good when I took them off valves defiently a little tight but still moved, and I only had one valve seal with a slight tear burning oil but all the seats were good otherwise no burnt valves. ive got the machine shop stepping on the heads now, and checking for cracks and warp. I'll probably do the porting myself to save $ just clean up the cast a little bit.
its a freshwater boat im on the IL River about an hour and a half south of Chicago
#15
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Joined: Oct 2013
Posts: 2,888
Likes: 148
From: SF Bay Area
Just a short list of some hard parts that are very popular here.
forged internals
Crane 731 cam or similar. Keep the LSA @112° or higher
8.5:1CR for cast iron heads with iconel valves
edelbrock air gap intake
Fresh aluminum manifolds with an O2 bung welded into the risers to run a wideband gauge.
A wideband gauge is cheap and invaluable for tuning.
Party on!
forged internals
Crane 731 cam or similar. Keep the LSA @112° or higher
8.5:1CR for cast iron heads with iconel valves
edelbrock air gap intake
Fresh aluminum manifolds with an O2 bung welded into the risers to run a wideband gauge.
A wideband gauge is cheap and invaluable for tuning.
Party on!



