LSJ Mean Mini Jetboat
 

First, I am going to apologize for a stranger posting about some random ass project. I know how irritating it can be when newbies join a forum and start blasting with problems without doing there own due diligence in research. I'm been digging around with this project since spring, more thoroughly lately.

Now for the project:

Attachment 16728

Putting an LSJ in front of a two stage hamilton pump in an 11 foot jet boat.

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I'm hoping for some help with ECU choice. I have been weighing the advantages of P17 vs E67 vs other stand alones but I was hoping with your wealth of knowledge you may be able to shed some insight.

Typically these boats run a foot pedal, so I can keep the electric one or go LS throttle body with a stand alone. I'm not sure how the stock one will handle the odd splash. What other issues might I run into running the stock ECU running it as a stand alone? Right now I have been running it on the bench with the start relay hot and the fuel pump controlled with the key. I realize this isn't ideal because of fire, if the stock ECU could be up to the job I would pick up HP tuners and disable the VATS. I don't want to start spending on HPTs if a stand alone would be better.

I have spent a ton of time labelling and sorting the harness with the wiring diagrams on Autozone. If anyone wants a complete zip file of .jpegs let me know. I can put them all into a .pdf as well.

As LSJ Masters how would you do it?

Thanks in advance.

in for this !!

LSJ everything lmao amazing

click

the stock pcm should do the job cool project

Oh, forgot to mention it has to run in open loop all the time. You can't run O2's in the marine word with the water injection in the exhaust. I was planning on disabling them via the tuning manual and HP tuners.

Haltech platinum sport 1000

Looks nice

Welcome to Cobalt land, Once you enter there's no escape.

Where are you injecting that, as the main O2 sensor is located in the manifold. And no problem running the LSJ ecu stand alone, as I have one planted in a rear engined
European Opel Speedster. ;)
Just cut a few unnesessary wires out of the loom and you then need to switch a few things off in HPT. For starters the VATS settings.

The stock pcm can do it to a point but there really is not sufficant tables to really give it a good tune i would go stand alone

Just install the MAF.

I guess you guys don't see many marine manifolds. Here is mine. The water is injected at the band clamp. It looks like a tube inside a tube. 3" Straight pipe to the transom from there.

Attachment 16727

What's the water injection for? Is it to recapture exhaust power for thrust?

Any reason why you cant vent to atmosphere?

As I understand it, in a boat you don't have the airflow you do in a car. Temperatures in the engine bay can get quite hot and melt wiring/coolant lines etc or start a fire. The injected water keeps the exhaust tubing and all the couplers cool so you don't have to run a water jacket all the way to the transom.

i dont think he can run the maf

Would an average Joe notice the poor tune or just a well seasoned tuner? Standalone suggestions?

I have been quoted $1500 for a MEFI 4B unit without an LS throttle body. I'm thinking about giving the stock a go then just test some other systems.

What issues might I run into? I was looking at using a weld in MAF mount from ZZP with a 3" K&N mounted in a box which is vented outside the engine bay.

i miss understood i thought you were refering that you couldent run the maf or o2 sensor which would put you into speed density

I was able to get the manifold on the engine last night. Ran into some issues. Any issues with running a 2.2 thermostat housing and using the heater core spigots to the oil cooler? A 2.2 should clear right?

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Nice project, and great engine choice :)

Didn't see much room for a fuel tank. Cool Project though! :)

The plan is two 36" x 12" x 6" tanks in the rear along the sides holding 42 litres each (2,592in^3). You really have to drive the boat before finalizing though some like weight in the nose others in the aft.

i doubt the 2.2 stuff will clear your best bet is to plug the heater core hookups

Interesting build!

I use a (european) 2.2 thermostat housing on my LSJ due to fitment issues, but ditched the LSJ sandwich oil cooler for a different type oil/water cooler. I only used the(modified) seperate LSJ oil cooler attachment assembly to connect my oil hoses to.