Alright guys I have an odd ball project, and I mean out there. I have an LSJ in a mini jetboat running the P12. I'll start by explaining some of the differences in installing an engine in a jetboat.
- The motor is directly coupled to the jet so it is always underload and the rotating mass is very high. Think massive flywheel with the clutch always dragging.
- The intercool is fed river water, IAT2 is almost always below 30C, unless the boat has been sitting. Generally the faster I go, the higher the boost, the more water it sees.
- There is no wind cooling the oil pan. All cooling come from a heat exchanger. I have a large one.
- Pedal throttle in the small boats; this is idea but the driver does get tossed around so it is tough to keep even pressure.
- The jet abosorbs a certain amount of HP at a certain hp. This is independant of speed. It's a constant thrust per rpm.
- The exhaust is water jacketed and water injected. No 02's. I can run the factory header with the hood off, but without wind it starts to glow very quickly. This is a large fire hazard for long term use.
I am having two issues right now:
1. Idle fluctuates once the engine is up to temp. I turned the idle up (1000rpm warm) to try and help the motor deal with the load but I still get a ~600-1300rpm fluctuation.
2. I am getting spikes in my injector duty cycle at WOT even though my pedal and commanded AFR are constant.
In the log it is idling until frame 115 then I tour around from there.
Attachment 54157 (Current Tune with Slightly hotter ignition which is actually worth about ~15hp (200rpm)
Attachment 54158 (Log file after a tour around the river)
Pump Power Absorption Curve (772 Standard 106 Curve)
Attachment 54159
