Carbs vs Fuel Injection

[Captain Dave T]

Hello All, I am looking to buy a 1995-2000 330/340 Sea Ray Sundancer. I really wanted fuel injected ( MPI. Horizon ) motors , but am finding them hard to come by. Can anyone give me some insight as to if it is worth a $10,000 premium for the injected motors ? . I know there is a difference in efficiency , but I can't find any numbers ? Thanks for any information.

 

[moparlvr4406]

IMO the horizons are very dependable...carbed motors are great but the injection adds dependability , runability and better response . carbed motors can be a bit cold natured on start up where with injection you just fire up and go.

 

[JimG]

IMO the horizons are very dependable...carbed motors are great but the injection adds dependability , runability and better response . carbed motors can be a bit cold natured on start up where with injection you just fire up and go.

+1 :thumbsup:

 

[mvoellinger]

Injection means if the engine can start, it will as soon as you turn the key. The downside is....20 million sensors that can wreak all kinds of hell on your boating day. Carbs are low maint. Anyone with an injected motor can tell you the time an IAC stranded them. With that side, I still prefer injected for the higher power and better efficiency.

 

[RollerCoastr]

Hello All, I am looking to buy a 1995-2000 330/340 Sea Ray Sundancer. I really wanted fuel injected ( MPI. Horizon ) motors , but am finding them hard to come by. Can anyone give me some insight as to if it is worth a $10,000 premium for the injected motors ? . I know there is a difference in efficiency , but I can't find any numbers ? Thanks for any information.

Your results will be driven largely by what model year you're looking at. '95-'97 330's are very likely to be carbed. Of course barring a retro-fit, the likelihood increases with the age of the engines. You'll see 330DA's with Horizons beginning in '98. I had a '96 330DA with the carbed 310 hp 7.4's. At NO time did I feel the need for more power in that boat. She jumped on plane and cruised very well, albeit with a stern-heavy attitude (as has been discussed at length on CSR, most people believe the 330 is under-tabbed, particularly with big blocks).

It also didn't take long to learn the starting routine: it requires more thought than FI, but certainly not $10,000 worth of thought! I would pump the throttle a few times and would have to let them warm up when fully cold, but I don't recall them ever stalling.

 

[alwhite00]

I went from a 5.7 carb in my old boat to a 5.7 EFI in this one and while I never had a problem with the carbbed 5.7 I really like the EFI on this boat. Starts instantly, No pumping. I wouldn't pay 10K for it though.

LK

 

[Creekwood]

I have the carbed 7.4s. Starting is never a problem. The carbs do leak down or dry if you dont start them for a week or more, but after cranking for a bit (maybe 3 to 5 seconds) then a couple throttle pumps, they fire right up. If they have only been shut down for a day or so, one pump and they fire right up.

I doubt that the fuel efficiency is much better with the fuel injected versions. "Fuel efficiency" is an oxymoron when you are talking about gas powered 15,000lb plus boats. I would bet that variations in wind, wave, speed, and driving style would have a much greater impact.

 

[GrandMaster]

Injection means if the engine can start, it will as soon as you turn the key. The downside is....20 million sensors that can wreak all kinds of hell on your boating day.

Bingo...only three things that will stop my engines apart from them blowing up...no fuel, no spark, or no air.

 

[IanBat]

As per previous start up, crank it for a while then a couple of pumps. More than happy with the carbs, and if I need to fault find it (which I havent yet) it is easy.

 

[Alegria]

I have the carbed 7.4s. Starting is never a problem. The carbs do leak down or dry if you dont start them for a week or more, but after cranking for a bit (maybe 3 to 5 seconds) then a couple throttle pumps, they fire right up. If they have only been shut down for a day or so, one pump and they fire right up.

I doubt that the fuel efficiency is much better with the fuel injected versions. "Fuel efficiency" is an oxymoron when you are talking about gas powered 15,000lb plus boats. I would bet that variations in wind, wave, speed, and driving style would have a much greater impact.

Yep Creekwood said it all. Especially the part around "Fuel efficiency". My burn ranges from 28 to about 32 gallons per hour on cruise depending on wind, current, and loading... I would not expect much less from EFI... I look on the bright side, when I go to a bigger boat my fuel burn in diesel will be similar!!! HA.

 

[xravenx]

I doubt that the fuel efficiency is much better with the fuel injected versions.

I can shed a little light here as I went from carbed 7.4s to fuel injected 8.1s.

Carbed 7.4s: 3200 RPM, 21 MPH, 31 GPH

Fuel injected 8.1s: 3600 RPM, 25 MPH, 31 GPH
3200 RPM, 21 MPH, 26 GPH

Dry wieght of a 370DA is 17,000 lbs. Also no pumping of throttles anymore, motors start instantly, Smartcraft is pretty cool too.

There is a 1990 350 Express where I store that did the same conversion 2 years ago I did and is seeing slightly better numbers then me.

John

 

[alwhite00]

I can shed a little light here as I went from carbed 7.4s to fuel injected 8.1s.

Carbed 7.4s: 3200 RPM, 21 MPH, 31 GPH

Fuel injected 8.1s: 3600 RPM, 25 MPH, 31 GPH
3200 RPM, 21 MPH, 26 GPH

Dry wieght of a 370DA is 17,000 lbs. Also no pumping of throttles anymore, motors start instantly, Smartcraft is pretty cool too.

There is a 1990 350 Express where I store that did the same conversion 2 years ago I did and is seeing slightly better numbers then me.

John

Nice comparison.

LK