Mercruiser MP Fuel Injection Systems

"I have a couple of Crusaders

"I have a couple of Crusaders with Quadrajets. One is reverse rotation. I see that Mercruiser offers new engines with MPFI. I was wondering if anyone could give me some info on these systems. For example:
Who make the system for Mercruiser?
What (if anything) does it use for oxygen sensor, wet, dry?
Any other info may help me decide whether to persue these systems for my engines or go to holley.
Thanks,
Mike"

"Mike;
I believe the basic EC

"Mike;
I believe the basic ECM is made by Motorola for Merc. The programming is by Merc and varies from engine to engine.
There is no O2 sensor, as it will not work in a wet exhaust environment.
The ECM operates blind without O2 feedback. So the programming is fairly basic and intended to cover a wide range of variable conditions for the given engine displacement.
Having said all this, they are a lot better at providing the correct fuel to air mixture than any marine carb, in particular the Q'jet, in my opinion.
Rod"

"Thanks Rod,
The Holley syste

"Thanks Rod,
The Holley systems seem to be designed for high performance. I just want to get better gas mileage. The boat performs very well with the Q-jets. I've got an email into Holley, but it seems likely they'll require a dry exhaust (they use oxygen sensors), which I can't do.

I'll look into the Merc system, hopefully they have an ECM for reverse rotation."

"Mike,

Both Mercruiser and

"Mike,

Both Mercruiser and Crusader have offered EFI for over 10 years. I don't know what engines you have but, to the best of my knowledge, no one has ever used them on RH engines. That doesn't mean you can't get it to work. You would need to be able to have the ECM reconfigured to fire the injectors at the correct time. You might be able to simply switch the injector wires around.

A TBI system may be an easier fit for you. Both systems are readily available used. They are always on eBay (for a lot less than the Holley system).

Good luck,
Rick"