Electronic fuel injection conversion

Does the manufacturer claim that system is approved for marine use. I'd be reluctant to consider it if it wasn't. Still seems like a cure for a disease that doesn't exist.

The system he is considering has a marine version.

https://www.holley.com/products/mar...ine/sniper_efi_marine/sniper_efi_4150_marine/

The question is the gain worth it? Figure a $1,000 for the Holley Marine Sniper and another $500 for a Marine EFI fuel pump so $1,500 per engine for the two main components. That's $3,000 before the labor and wiring.

If I use your analog the "disease" is fuel efficiency related to the engine's fuel system. Most factory engines with carbs are "close enough" that modifications to the fuel system don't result in material gains. That said, a lot of other things drive fuel economy (weight and bottom growth) more than the fuel system.

Still, getting as close as you can to 14.7 AF fuel mix means that you aren't wasting gas or sacrificing performance which is why EFIs generally beat carbs for efficient fuel use. That said.....a properly tuned marine carb/ignition system will perform equal to an marine EFI system on a dyno all day long. Boats are either idling (650 rpm), no wake (1,000 rpm) or at cruise (3,200+ rpm).

Cars vary their rpms all the time and EFI will do a better job of managing fuel and performance than a carb on a car.
 
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To all, right now just researching and asking questions, best thing I do. Holley states the throttle body is USCG approved. I found the link somewhere online, efisystempros.com , Holley system and that is when I became interested. My system is Rochester based. Just finished installing new water pressure system on boat and was curious about it is all. Holley makes a spreadbore to fit. The systems appear to be straight forward.
 
The system he is considering has a marine version.

https://www.holley.com/products/mar...ine/sniper_efi_marine/sniper_efi_4150_marine/

The question is the gain worth it? Figure a $1,000 for the Holley Marine Sniper and another $500 for a Marine EFI fuel pump so $1,500 per engine for the two main components. That's $3,000 before the labor and wiring.

If I use your analog the "disease" is fuel efficiency related to the engine's fuel system. Most factory engines with carbs are "close enough" that modifications to the fuel system don't result in material gains. That said, a lot of other things drive fuel economy (weight and bottom growth) more than the fuel system.

Still, getting as close as you can to 14.7 AF fuel mix means that you aren't wasting gas or sacrificing performance which is why EFIs generally beat carbs for efficient fuel use. That said.....a properly tuned marine carb/ignition system will perform equal to an marine EFI system on a dyno all day long. Boats are either idling (650 rpm), no wake (1,000 rpm) or at cruise (3,200+ rpm).

Cars vary their rpms all the time and EFI will do a better job of managing fuel and performance than a carb on a car.
Thank you. Now to find a good mech who can get my carbs tuned to that desired mix.
 
So, I sent a mail to the pro at Holley, I had read that Holley was not getting into marine fuel systems, but since they obviously have components certified?? I also looked at Moeller since they appear to be the biggest for fuel senders et al.
For return line issue, I was thinking someone has to make a drop in pump with universal fitting that encompasses a return line, just thinking. It is logical to me.
 
I looked at the exact same conversion last year and the trick part is plumbing the return line. The guys at offshoreonly.com used one of three methods:

-Hole in tank (which I would never want to do)
-T fitting to fill hose (noted above)
-connect the line to the input spare port on the Water Separator

The O2 sensor is not a problem. It will raise the riser height about an inch on one side of the engine. Aluminum plates are available on Ebay and work great.

Where I ended up was going old school/new school. It is really difficult to fine tune carbs on a boat reading plugs. So, I installed two Air Fuel gauges with wideband O2 sensors on each engine. This gave me instant AF data on both engines which allowed me to change the jets to run close to 14.7 at idle and around 14 with the secondaries open.

I have been running 76s (primary) and 82s (secondary) for years. With the AF gauges in place.....I am running 74s and 76s respectively. The setup will probably pay for itself in the cost of gas.

If you think about it....that is what fuel injection is all about.....tuning the mixture to get as close and consistent to 14.7 that you can.

https://www.ebay.com/itm/AEM-X-Seri...:lEYAAOSwNPdbpyS3:sc:USPSPriority!22124!US!-1

https://www.ebay.com/itm/OXYGEN-SEN...451597?hash=item4b15de844d:g:NIkAAOSwWiBY-RWT

($178 gauge + $78 adapter) x 2
So not having taken risers off, Is it difficult?
 
But, but I love my boat! My GF says I like my comfort too much. Just the right fit, I can tinker, relax or go exploring. I can also sit at dock and do nothing. I prefer to consider what can be done without drastically changing it. That is why I ask questions.
 
Thanks to everyone for answering. Sincerely appreciate the suggestions and opinions. Also the stuff learned today. Thanks.
 
I realize this is a probably a late post but:
Holley states the throttle body is USCG approved.
If they said that they are mis-informed. Ask them for the approval number. They won't be able to give you one because the USCG does not approve these kinds of systems. They are self certified. That is: the manufacturer has to certify that it meets whatever regulation applies. In this case the only regulation that applies would be that it doesn't leak fuel into the boat.
What their web sites says is:Certified to ISO 8846, SAE J1171 & United States Coast Guard Requirements for Ignition Protection & Fire Resistance. Making Sniper EFI the perfect choice for carburetor to marine fuel injection conversions!

That is not Coast Guard approval.

Sales people have a bad habit of saying"it's Coast Guard approved", when really it isn't. If it was it would have to be labeled on the device with an approval number. Look on older Flame arresters. They will have an approval number, Approval Nos. 162.015 or 162.041 or engine air and fuel induction systems bearing basic Approval Nos. 162.015 or 162.042
newer ones will say SAE J-1928 or UL 1111

But you will not find that on a throttle body or Fuel injection system because they don't do approvals on those.
 
I realize this is a probably a late post but:

If they said that they are mis-informed. Ask them for the approval number. They won't be able to give you one because the USCG does not approve these kinds of systems. They are self certified. That is: the manufacturer has to certify that it meets whatever regulation applies. In this case the only regulation that applies would be that it doesn't leak fuel into the boat.
What their web sites says is:Certified to ISO 8846, SAE J1171 & United States Coast Guard Requirements for Ignition Protection & Fire Resistance. Making Sniper EFI the perfect choice for carburetor to marine fuel injection conversions!

That is not Coast Guard approval.

Sales people have a bad habit of saying"it's Coast Guard approved", when really it isn't. If it was it would have to be labeled on the device with an approval number. Look on older Flame arresters. They will have an approval number, Approval Nos. 162.015 or 162.041 or engine air and fuel induction systems bearing basic Approval Nos. 162.015 or 162.042
newer ones will say SAE J-1928 or UL 1111

But you will not find that on a throttle body or Fuel injection system because they don't do approvals on those.


Just curious....."self certification" equals liability. It would seem that most of the marine industry has moved to self certification (or third party certification) since the USCG is in the specification business.

I wouldn't hesitate to use any of Holley's marine products on a boat. Do you know of a single problem where their marine products did not meet the USCG specifications.
 
I wouldn't hesitate to use any of Holley's marine products on a boat. Do you know of a single problem where their marine products did not meet the USCG specifications.

No. At least not while I worked in the USCG Office of Boating Safety. Frankly, I would trust Holley products too.

Almost the entire regulatory requirements for recreational boats is set up for self certification. The USCG would have to have a small army of inspectors and contract test labs, and a much bigger boating safety budget, to test and approve all of the boats and marine equipment that exist. So back in the 70's after the Federal Boat Safety Act passed, it was Congress's intent, and the USCG, that it would be self certification. There are a few things, mostly left overs from regulations prior to 72, that require actual Coast Guard Approval, and even those are contracted out to test laboratories, such as Underwriters Labs. Flame arresters used to require Approval, but that changed in the early 2000's, Now the manufacturer must submit an example to UL for testing. If it passes then they have to label it as complying with UL 1111 (the UL standard for flame arresters)

The flip side is, recalls. If a product does not meet a standard, which can be determined a number of ways, then the USCG can require the manufacturer to do a recall. That can get really expensive if the item is a boat, because the law makes it the boat manufacturers responsibility for all expenses, including transporting the boat.

And as was mentioned, liability. If something bad occurs, the manufacturer of the item, the engine manufacturer, the boat manufacturer (assuming this was installed on a new boat as it came from the factory) can be held liable. If the item is aftermarket and installed by the owner (or a marine mechanic) then liability is on the item manufacturer and maybe the mechanic who installed it.

And on most things the USCG doesn't specify how it must be made. Most of the regs are performance standards. Example, ignition protection. The reg says (paraphrasing here) it must not ignite a fuel air mixture at such and such a concentration when test in accordance with UL or SAE test XXXXX. How the manufacturer designs the product to achieve compliance is up to the manufacturer. a subtle distinction between a specification and a performance standard, but the later allows for innovation. If a manufacturer finds a new way to make something, as long as it meets the performance standard, thats ok.
 
Thank you for providing a great explanation of stuff. I emailed Chris at Efisystempro, Their system is what I have looked at. He will be at Holley later this year to discuss system. Gonna wait until a better system is available and decide then about anything. I do appreciate every response. Thanks to everyone, now I understand a lot more than before.
 
I’m a streetrodder and hotrodder too. I looked at various EFI systems too. Andvasked the same question regarding the O2 sensors. I use O2 sensors and AFR Gages on my streetrod and have used the race mechanical FI systems as well.

As a newbie in the big boats I quickly learned the advantage of the old carbs. I had a motor quit just before dark out on the Miss River. One thing with big boats here is you don’t want to get out of the channel ever and especially at night.
I had a friend on board who had never piloted a big boat let alone a big cruiser. I said just hold it in the channel facing up stream. Red bouyb on the right green on the left. I then opened the hatch to the dead engine. I suspected water in the fuel as I had the problem before and thought I had fixed it.
I carry at least 6 extra fuel/water separators so I turned all the blowers on and carefully unscrewed the separator over a large plastic coffee container. I dropped the filter in and closed the top. Then screwed the new one on and opened the shutoff valve. I also have a priming syringe and small amount of fresh gas so I filled the syringe and pumped a little down the carb vent and a little in the carb throat. Reinstalled the flame arrestor and closed the hatch.

Up on the bridge a short pump with the throttle and hit the key. The motor started right away coughed then caught and ran. We then traveled at sub planing speed to our marina some distance away.

This is where EFI would have faltered. Getting water in the system is simply out if the question. There would be no easy way out of this one.

My pier neighbor has found out the hard way about water in the fuel. It’s incredibly humid down here on the waterfront. The boat literally rains water every morning. You can imagine what happens in low fuel tanks. I’ve since made a tank pumping kit to pump the bottom of the tank periodically.
The old carb has been around for vabout a hundred years so it’s been worked over quite well. It can pass a little water and survive with a little help. EFI not so easy.

Performance wise I doubt there would be any power gain. Mpg, well

1 mpg vs 1.25 if that would not be worth it. It would take a lot of cruising to make it cost effective especially 2 motors.
 
I’m a streetrodder and hotrodder too. I looked at various EFI systems too. Andvasked the same question regarding the O2 sensors. I use O2 sensors and AFR Gages on my streetrod and have used the race mechanical FI systems as well.

As a newbie in the big boats I quickly learned the advantage of the old carbs. I had a motor quit just before dark out on the Miss River. One thing with big boats here is you don’t want to get out of the channel ever and especially at night.
I had a friend on board who had never piloted a big boat let alone a big cruiser. I said just hold it in the channel facing up stream. Red bouyb on the right green on the left. I then opened the hatch to the dead engine. I suspected water in the fuel as I had the problem before and thought I had fixed it.
I carry at least 6 extra fuel/water separators so I turned all the blowers on and carefully unscrewed the separator over a large plastic coffee container. I dropped the filter in and closed the top. Then screwed the new one on and opened the shutoff valve. I also have a priming syringe and small amount of fresh gas so I filled the syringe and pumped a little down the carb vent and a little in the carb throat. Reinstalled the flame arrestor and closed the hatch.

Up on the bridge a short pump with the throttle and hit the key. The motor started right away coughed then caught and ran. We then traveled at sub planing speed to our marina some distance away.

This is where EFI would have faltered. Getting water in the system is simply out if the question. There would be no easy way out of this one.

My pier neighbor has found out the hard way about water in the fuel. It’s incredibly humid down here on the waterfront. The boat literally rains water every morning. You can imagine what happens in low fuel tanks. I’ve since made a tank pumping kit to pump the bottom of the tank periodically.
The old carb has been around for vabout a hundred years so it’s been worked over quite well. It can pass a little water and survive with a little help. EFI not so easy.

Performance wise I doubt there would be any power gain. Mpg, well

1 mpg vs 1.25 if that would not be worth it. It would take a lot of cruising to make it cost effective especially 2 motors.



I would not expect a 25% improvement in fuel consumption with EFI conversion. Somewhere in the 5-10% range would be more like it. A 25% reduction of fuel in the combustion chamber would result in burned valves and pistons.
 
I think the smart thing to do would be to get the water out of the tank instead of bringing half a dozen gas filters with you and then saying efi sucks.
 

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