automotive EFI is not SAE 1171 compliant. so while some people do not understand the simplicity of a carb, suggesting using automotive EFI in a boat is simply bad advise
I do understand carb. I also know EFI is superior, and safer.
your photo is showing a boat exploding, something that can happen when you get an explosive mixture of fuel in the air in a contained space and an spark sets it off.
a carb has several vents to atmosphere the biggest being the bowel, a warm engine will aid this liquid in from becoming a liquid to vapor and then you get above. that's why you turn the blower on for a few minutes before you start the motor. most carb boat smell like fuel for this reason.
with EFI you have a high pressure pump that sucks it from the tank and pressurizes it up to a closed valve (the injector) and a return pressure regulator that goes to the tank. no vent to atmosphere. in the case of the 4.3L vortec it's just like its big brother with spider injection located inside the intake manifold behind the throttle body. A leak here would be sucked into the motor, if the motor dies from to much fuel the computer shuts the pump off... so how are you going to get a leak of fuel vapor that can cause an explosion? you have to use the correct fuel line for this because you are now at 60psi vs 8psi, there is your other fail point. so give me a more scientific reason why EFI is unsafe
when you are setting a carb, you set the to run rich at idle so when you put it in gear the load will not stall the motor. then you have to play the game of setting your jets and metering rods to give you a good hall shot, throttle response, and tip in and top end. and you have to pick what you prefer the most.
with EFI you don't have these problems you have a computer running 20+ million instruction per second (20MHz) who's whole job is to read the sensors (TPS,IAT, MAP, MAF, RPM, o2, Coolant, oil pressure) on the motor, look up tables, do math and spit out an answer (injectors & Timing). rinse, wash, repeat. the computer is mapped to cover large engine operation conditions. better fuel econ and power output.
so other than saying it wont work and point to a spec, give me a more scientific reason why you can't use it.
do you worry about your car/truck exploding and or catching fire when you take it out every day? didn't think so.