repower 5.0 MPI

[waterboy]

We are repowering our 5.0 MPI with a 5.0 carb motor. I understand there will be a slight HP loss, which I am not concerned about. What I need to know is how the new motor will adapt with the SmartCraft computer. Is there an adaptor for the wire harness?
Thanks,
Waterboy

 

[fc3]

No. It's impossible. The EFI computer on the engine drives smartcraft. Simply put the EFI module is smartcraft

 

[AKBASSKING]

I have heard of going from carb to EFI, but not the other way. May not work if your computer controls other things other than your engine (ie transmission).

 

[fc3]

cheaper

 

[boatrboy]

cheaper

That is the reason I am expecting to see. I would never go back... but that is just me.

 

[tdappleman]

Depending on the year of the replacement motor - why not just swap the intake, senors and other parts and essentially use just the parts off the new motor you have to use? You could then probably sell the intake/carb combo + other parts if you don't have another use for them. I'd love to have FI on my motors - just much less to deal with.

 

[jitts3]

I prefer old school carb over TBI, EFI, MPI Whatever, easeir to work on or with. Sucks to be down for sensor trouble. My .02

Advice. Consider everything. all guages, wiring and throttle cable will proplably be different. After changing it all over. it will be more expensive that you think.

I did this to a 89 Caprice. The computr just went along for the ride. Was just unplugged and added 1/2 pound to the lead sled.
Point it once converted back to carb, the ECM (Computer) is useless. But hey you could sell it.

 

[tobnpr]

What happened to the three year old engine that it needs to be replaced?

 

[fc3]

Advice. Consider everything. all guages, wiring and throttle cable will proplably be different. After changing it all over. it will be more expensive that you think.

He's right. All of the gauges on the helm are driven by the smartcraft engine CPU. You need to change the tach, temp, oil pressure gauges. You may possibly also need to replace the fuel gauge and speedo. Might also have to replace any warning alerts too. Not sure about the voltmeter, but I would not be surprised if they all had to be changed.

Who sold you on this bad idea?

 

[dpmulvey]

We are repowering our 5.0 MPI with a 5.0 carb motor. I understand there will be a slight HP loss, which I am not concerned about. What I need to know is how the new motor will adapt with the SmartCraft computer. Is there an adaptor for the wire harness?
Thanks,
Waterboy

Consider a 5.7. Little loss in HP. Lower RPM cruise and probably the same MPG/GPH. Very cheap and sometimes cheaper than a 5.0 because they are more plentiful.

I understand your reasoning.


Good luck.

 

[waterboy]

I've been gone for awhile. Thanks for all your posts. Reasons for considering the switch are: 1. price, 2. simpicity, 3. This is a boat club boat, gets used hard. 4. Because its a club boat, were not worried about HP loss, most of these folks would scare me with a four cylinder.
Although less than three years old, the motor had 1,300 hrs., someone sucked up a bag, overheated enough to warp heads, and broke a connecting rod. (and no alarm ever sounded)
We don't expect to get much resale value anyway.
I understand that I would at least have to switch out the gauges, hadn't thought about the throttle cable.
We're still weighing our options, starting to seem like more hassle than its worth, but I've lost alot of confidence in the MPI.

 

[jitts3]

MPI proplably not the trouble. Being beaten and not maintained will do it. Whoever hit the bag doesn't check guages?