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How are you going to plumb the inner cooler? It would love ice cold water. I guess if you are out of cold water ports you could do a simple secondary supply thue a sea strainer. Latham Marine
For reference the mefi stand alone computer is a Mercury/Mercruiser marine controller. It's so perfect. I know you will continue to dick with the stock stuff but if you eventually swap, my tunner had to swap knock sensors to one that the mefi can read.
My plan is the incoming water from the jet will go through a strainer/sand trap then through the inner cooler and off to the heat exchanger. Water will be between 1 and 5 deg C. The joys of playing in glacial fed rivers.
I went to a Delphi stand alone unit (MEFI: Marine Electronic Fuel Injection. This was made for marine applications) and switched to an LS cable throttle body.
Thanks. I guess to go Delphi I'd have to put the stock manifold back on, run it with a wideband to tune it, then put it in open look and put the marine manifold on.
JBM and Exact Welding have both put these motors in boats. Exact Welding is close by in Prince George. I bought the jet unit from them. I believe both used the module available from NZ. I don't recognize the packaging though. Let me know if you recognize it.
I know it wasn't easy and Exact had to send some sensors over to NZ to make it work on the LSJ. They only advertise it for the 2.2 and 2.4 with an LS TB swap.
Cut a big hole in the transom last night for the pump. It gives good scale that this pump is the smallest that will hang onto an LSJ. Hamilton 772 intake with Flo-Pro 19 bullet overlap leading and 19 standard trailing with a 106mm posi-nozzle. Flo-Pro Stainless stator and tailcone as well.
How much do you think the drive and its rigging weigh? What sites do you reference to pick nozzle selection, x- dimention (drive height) and such?
It all comes from the Hamilton manuals but the best resource from an old man with experience. More stages give move traction in aerated water. Other than that it's just a dyno; it absorbs power based on pressure and flow.
Here are some photo updates. I've been working in camp a lot lately which has slowed progress.
Congratulations! That thing pulls straight out of the hole and goes great! Your at full torque at 2200 rpm so I wonder if you could pull more pitch or do you need that much bottom end in your use? Any thing over 2200 pulls like a 350hp+ turbo or N/A motor in the sand. If your reving more than that at cruise then don't be afraid to pitch it up and discard the HP/pump selection used by inferior motors. It's hard to tell from sound but as perfect as the planning, attitude and weight balanced looked you might unlock a real monster when it's tweaked. Seat time will tell. You don't need 3500rpm to get it to hit and pull. Under 1800 and it dogs out fast. You car guys may need to know that boats are single speed and everthing is set by RPM. On a regular boat you select prop or in his case impeller pitch at WOT RPM. They give a +-300 RPM range printed on all marine engines. If you too doggy out of the hole you want max recommended RPM on top for example. He would not be worried about milking max speed and is why I'd pitch it so at the slowest speed he will need the explosive power it needs to be at 2100. It's easy to feel. To nail it out of the box on such a unique build would be tuff but It looked good! Thanks for the update.
Thanks guys! It was WOT on the one pass, and on the launch out of the hole. I haven't hooked HPTuners up yet so I'm guessing the pcm is having a spaz back there without the o2's or emisions sutff. It' impellored to only load the motor down to 4200rpm max with cruise being sub 3000.
The best way to think of a yet is a constant amount of thrust. I can pull 4200rpm sitting on the trailer at the boat launch or at top speed(no speedo yet sorry). The more power you make the more thrust you can make.
Looking at ordering a stage 2 kit with HPtuners and going to a return efi system. It's such a bitch to get all the air out of that fuel line.
I gave up with the tuner and paid the best dyno shop in Phoenix. Best grand I spent. Drop it off and say fix it. They made adjustments, changed sensors and made changes nobody else thought of. Not even the tuning software company or the mefi computer and harness supplier. When dyno results are right in your face there is no more guessing. 2.9" pulley and 42lb injectors allow for safe long pulls that never end like yours is doing. Personally I'd skip the pulley and start with that high dollar crank balancer pulley. It over drives like a smaller charger pulley but you have to do a little math and swap both pulleys to achieve what would be equal to something over a 2.8" supercharger pulley. See if you can grind the cover necessary for the balancer install with out pulling your motor first. Ditch that heavy internal balancer shaft as well to save weight and help it spin up.. Keep the stock heavy alt pulley. You need that spring. I tuned for 100 octane and would recomend that if you have a local airport near by. Do the math on cost difference. It's a bargain for no more fuel than you burn in a toy. If not maybe you can mix a few gallons of leaded race gas to help it out and keep it safe. We boost for way way longer than a street guy and that fuel is like I said a real bargain.
I gave up with the tuner and paid the best dyno shop in Phoenix. Best grand I spent. Drop it off and say fix it. They made adjustments, changed sensors and made changes nobody else thought of. Not even the tuning software company or the mefi computer and harness supplier. When dyno results are right in your face there is no more guessing. 2.9" pulley and 42lb injectors allow for safe long pulls that never end like yours is doing. Personally I'd skip the pulley and start with that high dollar crank balancer pulley. It over drives like a smaller charger pulley but you have to do a little math and swap both pulleys to achieve what would be equal to something over a 2.8" supercharger pulley. See if you can grind the cover necessary for the balancer install with out pulling your motor first. Ditch that heavy internal balancer shaft as well to save weight and help it spin up.. Keep the stock heavy alt pulley. You need that spring. I tuned for 100 octane and would recomend that if you have a local airport near by. Do the math on cost difference. It's a bargain for no more fuel than you burn in a toy. If not maybe you can mix a few gallons of leaded race gas to help it out and keep it safe. We boost for way way longer than a street guy and that fuel is like I said a real bargain.
Have a look at where Smithers, BC is on the map. The nearest dyno with a useful tuner is greater Vancouver area which is a 10-13 hour drive.
We do have an airport nearby but out on the rivers where the boat is going there is nothing for hours. If I ever had a fuel leak or ran out I'd be done. The nearest 94 pump is an hour away in Hazelton. Being realistic, I don't want to have to go to the airport before going out for a quick evening rip. I want to hook on, stop at petro-can, fill the boat and the truck and hit the river. I have to get the most I can on 91.
I was really hoping to go mefi4b but the company I was going through couldn't follow up on a wideband that was compatible with the software. I'd have to watch the gauge on the dash and try to make corrections. Nothing else seems to be able to read that stupid reluctor wheel and cam sensor combo that's in the lsj. the XFI Marine looked awesome and might be the way but I have to modify the cam sensor and add a trigger wheel.
Not trying to shoot down ideas, I'm just trying to paint the whole reality of my situation. I live 203km from the nearest walmart and 371km from the nearest mall.
371 km from a mall? Now I'm jealous! I was into hard core Jeeps back in the day before rock crawlers. We had a saying. "Run what ya brung". You just deal with what you have and used junkyard or home built parts. No shame in that and just as fun. You will get good with that laptop I'm sure. I got good when I listened to my tuner. He said to stay the heck away from it before I screw it up. Once dialed in you will feel sorry for the guys stuck with such a great running engine in a car. I ordered new custom cut paddles for the sand rail today. Kind of like a prop for the sand. Lol . Out of the box or mold they have two size paddles. You cut off the one you don't want so I cut off the smalrr ones. Next they will comp cut them. That's removing all the rubber down to the cords to make them light. My top secret is every other paddle will have the side of the scoop cut off so it power slides better. Boat, Jeep, car, dune buggy or lawn mower. It just ain't right until you mod it and tweet it. Good luck and thanks for sharing that bad ass fun machine with us.
I just found this vid on the alloy boat forum. It shows a small jet boat kit that is a pile of metal to plates to the guys out having fun with them. Looks like they just used tweaked jet ski motors but the concept is the same and the vid of them driving is great.
Get HPT working on the stock PCM and you can tune it as you need. There are serveral of us on here that could help with the tuning if you have basic abilities, and you can always get a remote tune done if you want, as long as you have your own HPT setup.
Also, just a thought, but you could switch to a lighter flywheel (I was thinking an auto flexplate from an HHR SS but that might be too light) for better initial response, you don't have the clutch/stalling issues to think about in your application.
I'm ready to start building one of these, looks so much fun. How is the cooling system done, heat exchanger to raw water from the jet pump?
I guess should have updated this thread again. HPTuners in running great and I've made some changes to the map to run a 3" pulley on 42# bosch injectors. I also made an excel to convert all the ford offsets into GM ones. I have a 2.7" pulley on now but the lakes and rivers froze up before I could get out with it. The boat is a missile.
Stumpalump: That boat was built by Thomas Hewitt and the hull was designed by Leighton Neal. It was one of the first jet dinghy's to emerge. I build my first hull modelled after that design with the intention of powering it with a CBR motor. I ended up using a Kawi 650 instead.
Also running straight river water through the intercooler is amazing. Unless I shut the engine off my IAT2 is almost always cooler than my IAT with the 3" even when pushing 13psi for 30-40min. It's only when the engine is idling and there isn't much flow that the intake heat soaks and the IAT2 climbs. Get back on step and it comes right back down.
03-13-2015, 05:48 PM
Moderator
and going to a return efi system. It's such a bitch to get all the air out of that fuel line.
