I'm in the process right now.

Just be prepared to do alot of the stuff yourself. There really isn't much available yet.

This is my first post so I don't want to cause any wake but.... There are TONS of parts available for all the LS motors. And with cyclinder head flow numbers comparable to big blocks you can make loads of power. I was doing some deep creative thinking (burnin') last night and asked the same question myself. Why not put a 400 pound complete motor instead of a 650 pound 455 in a jet boat? I'm new to jetboats and understand that you need to make the power down low in the RPM range but are there really any problems with running an LS motor?

Take a look at these puppies. CNC ported LS3 head for $1300
Don't forget to check out those flow numbers
http://www.mastmotorsports.com/2010/product-view.php?cat=Cylinder%20Heads%20-%20Assembled&id=360

I think he means as far as upswept headers, Engine mounts, etc

http://www.socaljetboats.com/boat-showcase/my-first-jet-69-schiada/msg153278/#msg153278

If you're serious about doing it, I've got a set of Mahle Blower pistons for one.......

Ray

Done a few hours of searching but haven't come up with anything conclusive. Who here runs a carb'd LS? What do you run for your fuel pumps/pressure regulator? If you're in OC I'd love to bring a beer or three over to check out your setup.

Compiling info to throw an LQ4 into my Caribbean for some sloppy junkyard fun after the 2017 season.

They work  someone will come along and tell you they wont work. they dont make enough torque, they dont make enough power etc

I have ran mine for the better part of 2 years now on a stock bottom end 5.3 with 218k miles on it. Granted i have 243 heads and a stout cam and valvetrain.

My heavy rogers runs in the 70's na with a C impeller

I have since built a new engine and havent tested it yet, but im expecting the same if not better. It dynoed 450hp NA and 633 on a 150 shot, not bad for 325 CI.

I run an electric fuelpump and regular Aeromotive fuel pressure regulator. I run a Daytona Smart Spark instead of a MSD unit because my MSD left me stranded. I changed brands

What do you want to know?

That was a damn good start lol. You're the second person this week to naysay MSD products. And that's from two completely different Motorsports too, the other was the Renezeders' truck. How's the Daytona compare with user interface?
What pump are you using? Brand,inline/in tank? What fuel pressures do you usually see?

I'm never one to immediately listen to someone saying something won't work. Especially when these swaps are popping up everywhere. I've got a set of 243 heads just holding down the floor in my garage, figured a junkyard LQ4 6.0 and a cam would be a nice start. My tired old 454 does probably 300hp and will get me to about 50 on the A impeller. And that's just me, the wife, and a cooler. Figured $2-3k would get me goin better than building or refreshing the BB.

That was a damn good start lol. You're the second person this week to naysay MSD products. And that's from two completely different Motorsports too, the other was the Renezeders' truck. How's the Daytona compare with user interface?
What pump are you using? Brand,inline/in tank? What fuel pressures do you usually see?

I'm never one to immediately listen to someone saying something won't work. Especially when these swaps are popping up everywhere. I've got a set of 243 heads just holding down the floor in my garage, figured a junkyard LQ4 6.0 and a cam would be a nice start. My tired old 454 does probably 300hp and will get me to about 50 on the A impeller. And that's just me, the wife, and a cooler. Figured $2-3k would get me goin better than building or refreshing the BB.

Ill answer your questions in order

1.What pump are you using? Brand,inline/in tank? What fuel pressures do you usually see?
 - Im running a Magnafuel 275, its a return style pump supposed to pull 18psi. Its very much overkill. Its external, and im running -10an feeds to a couple ball valves, into a magnafuel pre-filter into the pump. Then up to the Aeromotive regulators (nitrous and carb). Also have -8 returns. I have my Carb regulator set at 7psi and the nitrous flowed to 6.5psi

2. The programming is not as user friendly as the MSD but it has more features like Individual cylinder timing, more 12v accessories (retards etc) Once you learn it you are good

3. a LQ4, 243's and a nice cam will work very well. Sure as hell will work as well as your stock BBC maybe a bit better because of the weight savings. Exhaust choice will limit the cam choice though. I think mercruiser and a couple others sell cast manifolds. Lightning makes through transom headers, and Rewarder makes over the transom headers.

4. I used a SBF Sprint Car style header weld up kit with a set of LS flanges. The Port spacing is close to the same.

5. Im personally using a Rail kit and home made front/rear plates. I know for a fact a BBC rear mount should work, i just dont know about the driveshaft angle. But Tom is running a 3 point and seems to work well. He made some alternate mounts for the front that bolt to the LS Factory motor mounts.

6. Price... 2k should get you close. You can probably sell your BBC stuff and break close to even. You will need the following
- Mounts
- Exhaust (i built my headers, if you're going through transom you can get some SBF logs and drill/tap the heads)
-Ignition
-Fuel system
-PTO and maybe a driveline if you dont have a PTO style already
-Probably will need an oil pan, i run a LS3 camaro pan it holds about 8.5 quarts and gives me about a cunts hair of clearance

Bitchin. Thanks a lot for the info man. Most solid source of notes I've found without having to sift through all the bs talk about who makes what LS marine crate engine for $40k. 

Steve does your wiring harness have the OBDM attachment for mapping or did you by pass ?


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Gotcha" Nice, thanks Steve"


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Ya , that's what I'm having to deal with. It's nice to store data but it does nothing with a limited cam profile and the heads im running don't allow much change.


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Yup " throttle body 496 Vortec 


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