I now have 3 guys ready to switch over to fuel injection from carbs. I have been on line to holley and elerbrock talking to them about there systems. One has a kit to have throttle body and one has multi port with a new intake. My guestions are has anyone try to do this? Is it worth the switch? Two of them are charter guys and need the better fuel economy. Any info would really be great. thanks again dan

I believe,None of those sysems have any knock protection. I would rather have carbs with proper instrumation than have efi with no knock detection because if any piece in the system goes bad you have a trashed motor.One fuel injector bites the dust, time for a rebuild. If one map sensor bits the dust, time for a rebuild. Just to many pieces to an efi system not to have knock protection.
Allen

I don't think there would really be much of a fuel economy increase over a properly tuned carb, how many gph would you have to save to offset the cost of switching over?

I believe in fuel injection BUT for the 2500-4000 per motor you will spend I doubt you will ever recover a savings. You can bolt fuel injection on just about anything, I am putting a hybrid /home brewed efi on a 1974 Pontiac 455, I used a Edelbrock intake and rails, high impedance injectors and a ram jet 502 /zz502 efi harness and Mefi-4 controller. You can buy the controller and harness fairly cheap from GM but I still have close to 2500$ in the efi stuff alone, Smitty

Holley's HP system is excellent. I've done a half dozen of them this year with zero complaints. They have knock protection and anything else you can think of. There are a lot of reasons to convert to EFI but like Smitty said, for that application the fuel savings alone won't cover the cost. There are other good systems out there but the Holley ecm is waterproof, vibration, and shock proof like the MEFI.

How about driveability ??? Can't touch fuel injection in that area. My motors idle the same, whether 65 or 95 outside. Just tap the key and go...

unless you have some sort of magic carb, the only knock protection you have with one is the sound the pistons make when they hit the hatch cover...

you don't go to efi for economy altho that will be a meaningful and significant benefit. you go to efi for the advantage of having exactly and precisely the correct fuel curve for every single condition... so no fuel in the oil, no rich/lean anywhere at any revs. no carb made on this planet can do that. the motor lasts much longer , makes better power and has a much wider usable power band. assuming it is executed properly at installation and calibration, then there is no downside to it what so ever and the upsides are very significant.

Thanks for the help and support guys. The charter guys are the ones hurting on fuel economy. The one guy owns 2 - 30 ft sportcrafts one inj one not. On lake erie from vermilon river to the border and back the carb boat uses almost 20 gals more in a 36 miles round trip. Both are well maintained and both run side by side. In his case saving about a 125.00 a trip it might pay for itself quickly. thanks again dan

If at all make sure you go port injection.

You may want to look into using a GM speed density system.
Fairly cheap and parts are readily available.
You'll get closed loop fuel control and knock retard.

I've switched my Donzi over to this and it is nice.

Jeff