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whats truly needed to swap an ls engine

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whats truly needed to swap an ls engine

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Old 08-13-2013, 06:47 AM
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Default whats truly needed to swap an ls engine

okay so im torn between a 383 stroker running possibly afr 195 heads, or swaping an ls motor into my 21 scarab excel. If i swap the ls what do i fully need to get it into the boat? I would plan on the carb kit with the msd set up to run the ignition. I have found headers for it, i know the bellhousing bolts up to it. but what about motor mounts and cooling? I only run in fresh water. I'm looking at $4k+ easy for my 383 stroker. Then i still would want headers for that anyways. so is an ls with a cam, intake, and headers my better option, both money and power wise? I can pick up running 5.3's for $350 to $750. intake set up for it is $700 carb is $500, headers $2100. I just need info on cooling and getting it bolted into the boat. also i know i need a fuel pump to run it.
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Old 08-13-2013, 07:28 AM
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I'd do a 6.0 out of a truck Not much more money and lots more potential power. Sounds like you have it. You're have to adjust or fabricate motor mounts though I'm not sure.
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Old 08-13-2013, 08:53 AM
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rear mount, bell housing bolts up, though one bolt is a tiny bit off. Front mounts I believe use 4 bolts, while older motors used 3. you need all the computer stuff or if going carb a stand alone ignition. thats what Im sure of, you probably nned a cam but I believe a lot of the ls family, you can swap the cam without ripping the intake off
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Old 08-13-2013, 10:31 PM
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so can i just run raw water cooling for that engine or do i need to run a closed cooling system? i'd love a 6.0 with a stout cam.
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Old 08-13-2013, 10:42 PM
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Hardin has a seapump that works with the factory serpentine belt I believe. If it was me, and I may do some LS motors when mine are due, would go raw water in a freshwater application.
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Old 08-13-2013, 11:39 PM
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I've got an alpha drive still for now so would i still need the sea water pump? that unit is stunning piece of hardware but at 800.00 if its not needed yet... would the LQ4 cam in there now survive with a wet exhaust or should i swap one of the comp xtreme marine cams in? those range in form 300 to 500 for full kit with new springs. personally for now i wouldnt care if it was the 5.3 or the 6.0 once i have all the odds and ends i can always swap up to the bigger engine. yes i'd love the 6.0.
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Old 08-14-2013, 01:40 AM
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huh local salvage yard has 6.0 w 154k miles for 1000.00 and 99k for 1600.00 found a long block with 200k for 400. interesting... i found a raw water pump from sierra that looks exactly the same as the oem water pump?? I've heard of exhaust for 850 but cant seem to find them, the lightning headers are 2100.00 i guess the stock truck cam shouldnt have an issue with water reversion. so very interesting, that leaves the motor mounts and deciding on efi, tho that might be hard mounting 02 sensors in a wet exhaust. Odds are I'd run the edelbrock and msd system for pure simplicity. swap in a marine cam and i'd have a monster, granted i'd have to be gentile up until im on plane with the apha. hmm... now if someone only made motor mounts. I'm sure I can fab up a set.
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Old 08-14-2013, 07:28 AM
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No need for a seawater pump on the motor if you are running an Alpha drive.
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Old 08-14-2013, 08:59 AM
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I though I read that Hardin Marine was going to release a few accessories for the sbc/bbc to ls conversion crowd. IIRC that one of the accessories was a motor mount conversion.

LC
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Old 08-14-2013, 12:30 PM
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You can get adapter plates that adapt from the LS 4 bolt to the old style 3 bolt mounts.
You shouldn't need it with your Alpha drive, but Placecraft marine makes sea water pumps that bolt directly to the block and use the serpentine belt.
I'm running my raw water and have reworked the factory water pumps a little to work that way. I'm also using Placecraft manifolds. The lower manifolds were $250 each. I think the uppers were $150, but I built my own risers.
The bell housing works just fine, it's just short 1 bolt.

I'm running bone stock all aluminum 5.3s stock cams and intakes and all.
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