Originally Posted by gr82bgreen
You could run it without the sensors. it would be in open loop and would set codes, but it would run fine. The maf was not used on the older speed density system, but that system is calibrated to the car or trucks camshaft. I think the boat cam would run ok though. I don't know how the prograqming would translate form a car or truck, to a boat though. Ive heard its a bad idea to install automotive efi on a boat. probably cheaper and less headaches to upgrade to a new boat with efi. You would need lots of new parts, intakes, new fuel pump and lines, ecu, a wiring kit to make it work. would have to find a dry sealed place for the comupter.
If you disconnect the TPS, it will default to 12% throttle position at all times and that won't run "fine". If the MAP sensor is disconnected, the ECM will have no idea how much fuel to deliver, so that will default to a setting that won't allow good performance. If the ECT is disconnected, the ECM will think the engine is at about -40°F, or below, so it will run exceptionally rich. If the knock sensor is gone, it will want info, so it will prevent correct timing advance and throw a code, too. How does this qualify as "fine"?
A really easy way to upgrade to EFI is to buy a GM Performance Parts crate motor, like the 350 RamJet. 350HP/390Ft-lb of torque, it uses the same ECM and any GM dealer can service it when the warranty is still in force. The thing about MC- they calibrate teh engine to the boat, not a generic weight load.