Convert Chevy LS to marine use

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kens
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Location: Coastal Georgia

Convert Chevy LS to marine use

Post by kens »

A guy around the corner to me has a big Mastercraft, had a Ford in it, and trashed it. He swapped in the newer style Chevy LS street engine.
He started with a LS street engine,
he has the ($500) software to talk to the (EFI) computer
Software told the engine computer to disavow the car body side computer, now the engine runs EFI standalone.
Old school SBC bellhousing mates up,
manual clutch flywheel mates up to drive damper
Engine mounts came from auto engine swap parts, swap LS into older SBC, then use old-school SBC marine mounts
Raw water pump runs where power steering pump used to be
All electrical connectors are waterproof/watertight
Marine exhaust manifolds, starters, alternators are common available,
So now he got a aluminum block, alum heads, composite intake, EFI, high compression,
something like 400hp, and shed about 700lbs off from the cast iron Ford @ 285hp.
We've all seen the marine ready-to-buy LS engines for $15k-$20k, his manifolds at $1200 is more than all the rest of it combined
He's into it about $2k all in
interesting !
Oak..........the juice ain't worth the squeeze :D :shock: :o :)
hoodman
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Location: Lafayette, IN

Re: Convert Chevy LS to marine use

Post by hoodman »

Sounds like a hell of an upgrade.
Matt

Building a Geronimo......!
viewtopic.php?f=2&t=25139
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kens
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Joined: Wed Nov 12, 2003 5:25 pm
Location: Coastal Georgia

Re: Convert Chevy LS to marine use

Post by kens »

Yeah, it is,
Chrysler has their modern 'hemi'
Ford has their 'coyote'
Chevy has their 'LS' engine.
Glen L Witt designed the Crackerbox around the ubiquitious Chevy 350. (of the '50's-60's era)
I wish he was still around to design something around this Chevy LS series.
I am not a particular Chevy fan, but, in the last 20 years, the LS has come forefront of modern engine design.
And now, 20 years in, parts interchangeability has come in, they are cheap on the aftermarket.
And the Ole' man made his designs mostly around the street engine conversions of the day, for the 'Hot Boats' ........
I wish he could see this
Oak..........the juice ain't worth the squeeze :D :shock: :o :)
Hercdrvr
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Location: McKinney TX

Re: Convert Chevy LS to marine use

Post by Hercdrvr »

How do you figure the swap will shed 700lbs? Aluminum LS block is only about 100 lbs lighter than iron SBC or SBF.
Certainly doable, the exhaust manifolds are the big expense. I think you can build just about any marine engine for about $4,000-$5,000, depending on how many used parts you are willing to use. I saw Summit is selling reman 385 hp LS long blocks for $3250.
Matt B
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kens
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Joined: Wed Nov 12, 2003 5:25 pm
Location: Coastal Georgia

Re: Convert Chevy LS to marine use

Post by kens »

because he formerly had SBF cast iron, cast iron block, heads, intake, et., al.
His newer Chevy LS is alum block (100lbs) standalone weight, then add in alum heads, composite intake, all the other widgets,
the distributor is gone, the plug wires gone, the valve covers are a little alum pancake,
alum motor mount brackets, add it all up, it's accumulative.
And the manifolds are NOT expensive, they are comparable to existing SBF/SBC manifolds.
My point is that these LS engines are definitely more HP, definitely lighter, (you would expect to pay premium for this)
but no, these are 20 years in production now, and they have come into the cheap aftermarket parts
Oak..........the juice ain't worth the squeeze :D :shock: :o :)
Hercdrvr
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Joined: Mon May 11, 2015 12:52 pm
Location: McKinney TX

Re: Convert Chevy LS to marine use

Post by Hercdrvr »

Yes, after market marine LS engines in Glen L boats are on the way.
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kens
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Location: Coastal Georgia

Re: Convert Chevy LS to marine use

Post by kens »

Hercdrvr wrote: Sun Jan 09, 2022 6:11 pm Yes, after market marine LS engines in Glen L boats are on the way.
Are you promising that ?? :lol: :D
Oak..........the juice ain't worth the squeeze :D :shock: :o :)
Hercdrvr
Posts: 1772
Joined: Mon May 11, 2015 12:52 pm
Location: McKinney TX

Re: Convert Chevy LS to marine use

Post by Hercdrvr »

kens wrote: Sun Jan 09, 2022 7:40 pm
Hercdrvr wrote: Sun Jan 09, 2022 6:11 pm Yes, after market marine LS engines in Glen L boats are on the way.
Are you promising that ?? :lol: :D
No promises, twin V8’s in an 8’6” beam is no easy fit.
Matt B
hoodman
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Joined: Thu Nov 10, 2011 8:48 am
Location: Lafayette, IN

Re: Convert Chevy LS to marine use

Post by hoodman »

Do them inline and tie them together at the crank.
Matt

Building a Geronimo......!
viewtopic.php?f=2&t=25139
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