Fuel injection systems for Jet Boat applications

[HighRoller]

Very curious if there are any throttle body or EFI applications that are easy to tune and capable of the snappy throttle response you need for a jet pump application.

Or would a properly built and tuned high performance carb still be the way to go? Most of the injected engines seem to be a bit "doggy" off the bottom end. Of course it may be the fuel programming and cam selection...

 

[Crazyhippy]

Mechanical Injection was known for its snap, and efi should be even better... its all in the tuning though, the "self tuning" systems are marginal at best. DaveH should be along shortly to answer any questions you can think of.

Sent from my SAMSUNG-SGH-I727 using Tapatalk 2

 

[obnoxious001]

Very curious if there are any throttle body or EFI applications that are easy to tune and capable of the snappy throttle response you need for a jet pump application.

Or would a properly built and tuned high performance carb still be the way to go? Most of the injected engines seem to be a bit "doggy" off the bottom end. Of course it may be the fuel programming and cam selection...

EFI should outperform a carburetor throughout the rpm range because of being able to tune an ideal air/fuel mixture at any given RPM,, where a carburetor is more limited on tuning, so it gets tuned for wide open throttle, and of course the idle mixture gets adjusted, but the midrange does more or less whatever the carb is built to do.

The carburetor is still a reliable, simple way to go, depending on how involved you will be with installing and tuning your induction system.

 

[DaveH]

Very curious if there are any throttle body or EFI applications that are easy to tune and capable of the snappy throttle response you need for a jet pump application.

Or would a properly built and tuned high performance carb still be the way to go? Most of the injected engines seem to be a bit "doggy" off the bottom end. Of course it may be the fuel programming and cam selection...
__________________

there are lots of factors for "acceleration rate" of any engine. rotational mass, induction style, cam profile, ignition advance and other factors.

But in no way would a properly designed and tuned EFI system hamper engine performance or acceleration. the real advantage you would see over carbs on your engine would be at least 20% increase in fuel economy.

you simply have the ability to fine tune the engine to a much higher degree than with a carb and a distributor.

 

[HighRoller]

there are lots of factors for "acceleration rate" of any engine. rotational mass, induction style, cam profile, ignition advance and other factors.

But in no way would a properly designed and tuned EFI system hamper engine performance or acceleration. the real advantage you would see over carbs on your engine would be at least 20% increase in fuel economy.

you simply have the ability to fine tune the engine to a much higher degree than with a carb and a distributor.

So if you bought a good EFI system and all the necessary sensors/hardware...what's the level of difficulty on tuning if you had some dyno time? Better left to a professional?

I love tuning carbs...but now that I have a family I'd rather not have the occasional issues that come with them. (Stuck needle and seat etc...) Seems like EFI plus coil-per-cylinder ignition is the future.

 

[Forensic]

Out of curiosity.. Maybe a dumb question but I've never figured this out.

I've seen HP525EFI and intakes for sale on several of the forums in the past. I always wonder, can the EFI and Intake from a HP525 be transplanted onto a 454?
If this is possible, what modifications/upgrades would be needed on the existing 454 to accept this?

 

[rivermobster]

So if you bought a good EFI system and all the necessary sensors/hardware...what's the level of difficulty on tuning if you had some dyno time? Better left to a professional?

I love tuning carbs...but now that I have a family I'd rather not have the occasional issues that come with them. (Stuck needle and seat etc...) Seems like EFI plus coil-per-cylinder ignition is the future.

A dyno would be the best way to tune any motor.

How hard it would be depends on what system you buy.

Your best bet would be to talk to the shop thats gonna tune/dyno this motor for you, and see what system that they like best.

There are self tuning systems, and piggy back systems that work awesome too. I've had good luck with the Edelbrock EFI sytems. They are very easy to tune.

I helped STV_Keith develop a piggy back for Dyna Jet awhile back, and it self tuned and worked like a dream.

Ask 10 different people and you'll get 10 different answers.

Talk to whoever your going to use. :thumbsup

 

[DaveH]

So if you bought a good EFI system and all the necessary sensors/hardware...what's the level of difficulty on tuning if you had some dyno time? Better left to a professional?

I love tuning carbs...but now that I have a family I'd rather not have the occasional issues that come with them. (Stuck needle and seat etc...) Seems like EFI plus coil-per-cylinder ignition is the future.

tuning is tuning, no different if you had a carb, its just that you have a ton more adjustability.

the biggest problem i see is most dyno's cant run the engine exactly the way its going to be in the boat. different exhasut, different fuel delivery and so on. you get it running decent on the dyno, then drop it in the boat and the setup is now very different and it doesnt run that well. im not saying dont engine dyno it at all, because it gets you a lot closer to where you need to be, and you get shake out any possible oil leaks or minor issues before it goes in the boat.

EFI is like anything else. there is good stuff, great stuff, and cheap junk. generally you get what you pay for. the wire harness is critical, that is definitely something i would have professionaly done, unless you really know what you are doing and have all the different crimpers and connectors for making something of this nature and really understand whats going on.

 

[JUAN VONWERNER]

LOOKED INTO IT A COUPLE TIMES. $1500-$3000. ILL STICK WITH A WELL TUNED HOLLEY 750

 

[rivermobster]

tuning is tuning, no different if you had a carb, its just that you have a ton more adjustability.

the biggest problem i see is most dyno's cant run the engine exactly the way its going to be in the boat. different exhasut, different fuel delivery and so on. you get it running decent on the dyno, then drop it in the boat and the setup is now very different and it doesnt run that well. im not saying dont engine dyno it at all, because it gets you a lot closer to where you need to be, and you get shake out any possible oil leaks or minor issues before it goes in the boat.

EFI is like anything else. there is good stuff, great stuff, and cheap junk. generally you get what you pay for. the wire harness is critical, that is definitely something i would have professionaly done, unless you really know what you are doing and have all the different crimpers and connectors for making something of this nature and really understand whats going on.

Not sure who did your dyno work for you, but that statement is not quite correct...

When we do an engine here, it has the exact fuel delivery on it that it will run when it's installed. Thats the main point of putting an engine on a dyno, to make sure it's tuned right, and you have to have the correct fuel delivery to do that.

Normally, we use our own headers because they are already plumbed to messure EGT (exhaust gas temps) and AFR (air fuel ratio) to make sure the tuning it right.

If a cust. wants to check it again with his own exhaust, that can be done on the dyno as well, after the tune, to see how it affects the HP and torque readings. If anything goes way outa wack, it can be adjusted from there.

The dyno converter can also load up the engine at idle to simulate how it would run in gear.

Along with doing a proper cam break in, tuning is what a dyno was built for, so it's plug and play, once the engine goes in the boat.

HP and torque numbers can be manipulated by the guy thats running the dyno, so they may not always be true.

 

[spectras only]

This MSD system is for automotive application, but wonder if it could be used in jetboats with open engine bays? http://www.jegs.com/p/MSD-Ignition/MSD-Atomic-EFI/1718909/10002/-1?gclid=CNjMy_XO2LECFQQaQgodzVQAWw

The Holley marine EFI is probably the better way to go since it's priced comparably.

 

[steveo143]

I am currently converting the green Schiada to Holley Dominator EFI. It will use 2 4150 throttle bodies in place of the carbs with 8 225# port injectors.

 

[DaveH]

Not sure who did your dyno work for you, but that statement is not quite correct...

nobody "does my dyno work", i own my own dyno and do all my own tuning.

When we do an engine here, it has the exact fuel delivery on it that it will run when it's installed. Thats the main point of putting an engine on a dyno, to make sure it's tuned right, and you have to have the correct fuel delivery to do that.

well since you cant use the fuel tank(s) and entire delivery/return system that's in the boat, it is different. and different exhasut has a big effect on the VE (mapping) of the engine. in my OPINION, its not apples to apples.

LOOKED INTO IT A COUPLE TIMES. $1500-$3000. ILL STICK WITH A WELL TUNED HOLLEY 750
08-06-12 03:52 PM

i dont see how you could build a complete EFI system for less than 3k.

ECU, injectors, fuel pump, throttle body with flame arrestor, crank trigger, efi manifold, regulator and fuel plumbing, wire harness and sensors, i think 5k is a much more realistic figure. sure, you can go the junk yard route and scour sensors and OEM computers and graft it all together for a lot less than 5k, but its like anything else...... you get what you pay for.

 

[DaveH]

am currently converting the green Schiada to Holley Dominator EFI. It will use 2 4150 throttle bodies in place of the carbs with 8 225# port injectors.
__________________

heard good things about the new Holley system but havent tried one yet.

those injector sound HUGE, how much power are you thinking you will make? I REALLY like the Injector Dynamics ID1000 injectors. best injector i have ever worked with actually. i have 8 of them running at 80psi making 1400hp on a twin turbo motor with only about 60% duty cycle. their atomization quality is the beat I have ever seen, the thing idles and accelerates much smoother and cleaner than it did with other "typical" injectors.

 

[steveo143]

I am running E-85, I don't think 160's would be enough or would be close to 100% duty cycle. It is a 496 at 18# boost, around 1100 hp.

 

[HaxbySpeed]

heard good things about the new Holley system but havent tried one yet.

It's an awesome system. Really easy to use and durable.

For the OP, if you use the 900cfm throttle body on a decent single plane intake it'll support 600hp and the throttle response is very crisp. You can get a complete TBI setup for 2k and down the road if you want to upgrade to an MPI setup you can use the same ecm and main harness and just need a different injector harness. The ecm's are fully potted and CG compliant. You can download the software for free and check out how user friendly it is. The self tuning works great and you can turn off the O2 after it's done it's thing.

 

[HighRoller]

So just to educate myself and others...what Holley system are you referring to? I see they have several such as the Commander 950 and HP EFI. They bioth appear to be throttle body apps...is the Commander more expensive because it has port injection?

Also, do both of these systems require o2 bungs in the exhaust?

 

[rivermobster]

I've installed 2 of these so far and they both worked awesome. Super easy to tune since they come with an O2 sensor and feedback you can monitor.

Took maybe 10 min to tune on a new engine with alum heads, headers, cam and exh system redone.

The whole kit is right at three grand...

http://www.summitracing.com/parts/EDL-35000/?rtype=10

 

[rivermobster]

Found some pics if your interested in how it came out...

 

[Dave Wettlaufer]

454 Boat on Megasquirt - Colorado River - YouTube


What about Megasquirt?
http://www.diyautotune.com/

 

[HaxbySpeed]

So just to educate myself and others...what Holley system are you referring to? I see they have several such as the Commander 950 and HP EFI. They bioth appear to be throttle body apps...is the Commander more expensive because it has port injection?

Also, do both of these systems require o2 bungs in the exhaust?

I was talking about the new HP and Dominator systems. The HP is all you need and will run a T-body or MPI, almost any ignition, coil packs, dual knock sensors if you want, meth injection, etc.. It is a very powerful ecm that can also be used in a very basic form without needing much EFI knowledge. You do need an O2 bung in your exhaust but can disconnect it after it tunes itself and put a plug in or leave the sensor in and buy an $80 gauge for the dash that will show the O2 readings. Depending on the sensor location and exhaust it might not last too long though.

Here's a few Holley HP and Dominator EFI installs.

 

[parkerpowersports]

I JUST BOUGHT THE MSD atomic deal, has alot of tuning self adjusting deals for a/f mixture and timing control. dont see why it wouldnt work great on a boat but it only supports up to 650hp if i remember correctly..

 

[rivermobster]

Hey Haxby, real nice builds. :thumbsup

Have you ever tried the Edlelbrock system?

If so, how do they compare?

Thanks.

 

[Gelcoater]

454 Boat on Megasquirt - Colorado River - YouTube


What about Megasquirt?
http://www.diyautotune.com/

Hey! Look what the cat drug in. Welcome back to the madhouse Dave.:thumbsup

 

[Flyinbowtie]

I would like to do a twin throttle body deal on a tunnel ram, but haven't got an answer for the O2 sensor and wet exhaust. When someone figures out an aftermarket work around I will be listening. My Ski boat has a 350 TBI deal and no o2 sensor, and it runs excellent.
I know Merc can do it, just waiting for the aftermarket to do it and make it easy for the backyard guy to plug and play.

 

[rivermobster]

I would like to do a twin throttle body deal on a tunnel ram, but haven't got an answer for the O2 sensor and wet exhaust. When someone figures out an aftermarket work around I will be listening. My Ski boat has a 350 TBI deal and no o2 sensor, and it runs excellent.
I know Merc can do it, just waiting for the aftermarket to do it and make it easy for the backyard guy to plug and play.

CMI can make those headers for you. We had them weld in a bung on my friends Stoker, to do some testing for STV_Keith.

Never seen a dual TBI deal done, but if anyone could do it for you, it would be Keith I would think. It would be an interesting project for sure.

 

[HaxbySpeed]

I would like to do a twin throttle body deal on a tunnel ram, but haven't got an answer for the O2 sensor and wet exhaust. When someone figures out an aftermarket work around I will be listening. My Ski boat has a 350 TBI deal and no o2 sensor, and it runs excellent.
I know Merc can do it, just waiting for the aftermarket to do it and make it easy for the backyard guy to plug and play.

The fuel map that your 350 is running was developed using an O2 sensor. With most aftermarket controllers you can disable and remove the O2 sensor after you're done tuning and it will run just as good as your factory Merc piece. An O2 sensor isn't necessary for the operation of EFI but you'd have a hell of a time tuning without one.. Like Rivermobster said, CMI, IMCO, Stainless Marine, Dana, etc. All offer options for O2 bungs in their exhaust. It is also something that can easily be installed by any decent welder. If you're running single walled exhaust with water injection you'd only need to disable the water injection for an hour or so to get the fuel map dialed. The twin throttle body setup is no problem.

 

[HaxbySpeed]

Hey Haxby, real nice builds. :thumbsup

Have you ever tried the Edlelbrock system?

If so, how do they compare?

Thanks.

Thanks! I did a couple of the older Edelbrock setups with the little hand held controller and they worked well. I'm not sure what the latest stuff is like but I doubt it offers the features and control of the Holley. Also, the Holley ecm is fully potted like the MEFI boxes so it makes it very durable and resistant to heat, vibration, and water. It's also Coast Guard approved.

 

[Trash]

I would like to do a twin throttle body deal on a tunnel ram, but haven't got an answer for the O2 sensor and wet exhaust. When someone figures out an aftermarket work around I will be listening. My Ski boat has a 350 TBI deal and no o2 sensor, and it runs excellent.
I know Merc can do it, just waiting for the aftermarket to do it and make it easy for the backyard guy to plug and play.

Depending on your exhaust system you can have an O2 bung welded in the dry section or if your are running the stock type manifolds there are several people that make spacers that fit between the manifold and riser. The O2 sensor can be installed in the spacer.

Innovate also has a stainless steel pitot type insert that only allows the exhaust gas to get to the sensor eliminating any water or water vapor issues should you have a cam that's on the edge of reversion.

I installed the wide band gauge and can now monitor the AFR real time while I'm driving. I can't imagine not having it now.

 

[BoostPower]

👍we do em often.


Sent from My Boostpower Marine Efi Beacon.

 

[BoostPower]

[video=youtube;VDGOzaWxRis]http://www.youtube.com/watch?v=VDGOzaWxRis[/video]


Sent from My Boostpower Marine Efi Beacon.

 

[HaxbySpeed]

Yep, that Holley software is pretty slick and with free and easy sharing software it makes it possible to access anyone's computer anywhere. I don't even have to be at a computer that has the Holley software installed to be able to tune a customers engine.

What's the application in that in the vid? 7lbs boost cruising at 30% throttle is pretty serious! :thumbsup Why no intercooler though? That 215 degree MAT is scary. How much timing are you pulling to compensate?

 

[BoostPower]

It's reading 100 above amb. Intercooler is going on now! Usually it is 139. We can't simulate more then 100f in our DYNO room. Timing is pulling 6.
We primarily use Efi Technology with our software. How's that Daytona?👍


Sent from My Boostpower Marine Efi Beacon.

 

[Flyinbowtie]

Well I won't be able to afford to do this on the current engine, but when I build the 521 stroker for this boat (460 based) I will really try to make this happen through one of the board guys, sounds like STV Keith would be the one.
I want the traditional look of a polished tunnel ram on a jet boat, but would like the performance/economy of fuel injection. It would seem to me, in my relative ignorance of these matters, that a pair of throttle bodies on top of a T/R would look good, and with the proper tuning perform well.