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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 08-14-2013, 01:56 PM
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Do the LS...you won't regret it.

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Old 08-14-2013, 05:11 PM
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Y don't u just put a big block in it and be done with it. Parts much more available and make slot more power. I know guys that put them in 21' scarabs with no issues. It's gonna cost u a small fortune to do a ls motor once u get into all the knock knack stuff and it will still run better with a big block... Just my .02
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Old 08-14-2013, 05:32 PM
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hey wasted what did u do to that motor? you running the factory ecm? I'm guessing thats the 5.3? I can pick up a complete 5.3 with ecu and harness for 350 to 400. or the 6.0 for 1000. I know i could put in a big block or i could buy new rods for my 350 mag and be running for a few hundred bucks. I have a 5.3 in my avalanche and I'm impressed with what that can do in such a heavy truck. the ls is the future of small blocks. i just dont want to add all the extra weight of a big block. besides those tend to love fuel...lol
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Old 08-15-2013, 08:17 AM
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Originally Posted by Black Baja View Post
Y don't u just put a big block in it and be done with it. Parts much more available and make slot more power. I know guys that put them in 21' scarabs with no issues. It's gonna cost u a small fortune to do a ls motor once u get into all the knock knack stuff and it will still run better with a big block... Just my .02
Alpha Drive boat, big block not good. SBC would be the most bang for buck.
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Old 08-15-2013, 10:42 AM
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Originally Posted by Black Baja View Post
Y don't u just put a big block in it and be done with it. Parts much more available and make slot more power. I know guys that put them in 21' scarabs with no issues. It's gonna cost u a small fortune to do a ls motor once u get into all the knock knack stuff and it will still run better with a big block... Just my .02
I can't speak for anyone else, but my boat picked up 2-3 mph and had a lot better cold start and docking manners than the POS 454 i pulled out. I'm sure fuel economy was better too being sequential fuel injection, but i never checked.

Originally Posted by sdg0080 View Post
hey wasted what did u do to that motor? you running the factory ecm? I'm guessing thats the 5.3? I can pick up a complete 5.3 with ecu and harness for 350 to 400. or the 6.0 for 1000. I know i could put in a big block or i could buy new rods for my 350 mag and be running for a few hundred bucks. I have a 5.3 in my avalanche and I'm impressed with what that can do in such a heavy truck. the ls is the future of small blocks. i just dont want to add all the extra weight of a big block. besides those tend to love fuel...lol
No, 6.0L LQ4. Yes, I tuned the factory pcm with EFI live and converted it to open loop, speed density. Motor was stock with the exception of a small cam, springs, pushrods, LS1 intake, and tune.

http://www.youtube.com/watch?feature=player_embedded&v=mo0K0PWzj-o
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Old 08-15-2013, 06:00 PM
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well if I can tune the stock ecu to run in the same configuration as you have I probably could save 1300 not having to buy the edelbrock and msd set up plus a new carb. I'd rather have the efi personally. What cam did you decide to run in that? I think i may a bunch of sbc stuff to sell off...lol
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Old 08-16-2013, 11:34 PM
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I am slowly doing a conversion myself. PCM makes a 6 liter LS motor and I got the raw pump from them.
There are cast iron manifolds and aluminum available. Indmar has a few engine packages also..

I am doing the Carb with MSD igntion controller route, possibly blow thru Procharger, havent gotten
that far yet... i am looking for 400 to 600 hp , will need the procharger to get the 600...

My goal is to run in the 80's at no more than 5000 rpms...

One thing though if you run any salt water do closed cooling , they will rot out in a short time if you
have any salt going thru it with the aluminum heads.
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Old 08-17-2013, 01:13 AM
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I'm about 1000 miles from the nearest salt water so i dont think that will be an issue for me...lol yeah i understand what you're saying tho. we need a sticky with all the break down of how to do the swap and a listing off the needed parts and sites that offer parts. Lets face it the LS is the new era of engines. the old chevys have had their day and its time to accept it. these new LS motors are built above and beyond what any other stock block. they have cross bolted mains... think about that. a few years back only high end aftermarket blocks had that. these new heads flow unheard of numbers in stock form. and chevy was smart enough to make it so they kept nearly identical bellhousing bolt patters. They knew people would want these new motors in older cars as well. if ford had done the same with the new mod motors I would have dropped the new 5.0 into my old mustang instead of selling it.

that being said here is what i have found. One, if you are doing a carb conversion use the plain edelbrock intake and get the msd 6010 or 6012 box as the msd boxes are computer programable for custom tuning. Best of all its cheaper than the complete edelbrock setup, like $575 for the need parts vs $780 for the kit. two, they make inexpensive adaptor plates for motor mounts so we can use the existing mounts we have. three, lightning makes headers for these at $2100, you can get aluminum manifolds for $1450, or cast iron set up for $850. Four, you need an electric pump for fuel. not really an issue. Five Harden marine makes a sea water pump that bolts right up where the AC compressor mounted for 800.00 and you can keep your serpentine belt. not to mention that is one damn nice looking piece of hardware. Also from what I have seen, the stock truck engine cams seem to have the right LSA to not have to worry about water reversion. But for around $500 you can get a full cam kit from Comp cams. So for beween $2500 to $5500 you can have a full out LQ4 or similar 6.0 ls engine in your boat. you can go cheap and run cast iron manifolds and stock everything else. Or you can splurge on headers, even with headers your still only $3300!!! and sometimes you can find killer deals on engines for well under $1K.
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Old 08-18-2013, 11:33 PM
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okay one thing i forgot about is how do you attach your factory gauges to the ls block? Also since im running an Alpha one, how do I hook up the shift interupt swithc? guess thats one thing that might be important...lol I know normally it grounds out the distributor but on a DIS system... what the hell do I ground out??

Last edited by sdg0080; 08-18-2013 at 11:43 PM.
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Old 08-19-2013, 12:14 AM
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Bravo is ultimately the way to go...especially with LS. I just converted twin Pre Alpha/MR-1's to Bravo and ran the learning curve. You save big $$$ if you use a crank driven pump and pull suction through the Bravo. With more and more Bravo boats out there the prices are coming within reach of the average guy.Sandy left quite a few Bravo's available on the East Coast.You can beat on a regular Bravo I all day with a stout SBC or LS...you won't do much beating on an Alpha with a strong Vortec or LS.

Think it through and do a bit of comparison shopping...you'll be surprised.
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