EFI for everyone
12-12-2011, 04:58 PM
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I've installed an Edelbrock EFI on a SBC and the outcome was amazing. I gained a huge jump in performance and fuel economy over the stock motor. The car never ran so good. When I bought my boat the first thing I looked into was going to EFI. My problem is that I have Lightning wet headers and to add an O2 bung would be difficult and new headers with O2 bungs are about $2500 on top of the $3500 for a complete EFI system it was more than I wanted to get into. I have a few questions though, one system I haven't seen mentioned yet is the ACCEL DFI system. I have a buddy over at Kinsler fuel systems and that was the system they recommended to me. They have a marine rated system that is complete and can support over 650hp which is where I'm at. The other issue I saw was that most electric fuel pumps need to be mounted below the tank so they get a good siphon. On a boat that means placing the pump in the bottom of the bilge. Has anyone had a problem with this? Also what is the consensus on batch mode verses sequential. I've done a little investigating in some of the EFI systems and there is a lot to consider with EFI. You have batch mode and variations thereof and sequential mode. My concern is this, how well do some of these controllers handle things such as the wall wetting effect? Under hard acceleration, a portion of the fuel sticks to the walls of the intake port until air velocity increases with rpm. Some systems, specifically Mega-Squirt actually have a complex algorithm that adjusts fuel flow to adapt to this affect. If this is ignored you will be lean initially and then there will be a rich period until your rpm stabilizes. There is also the issue of injector firing timing, When running at full rpm you may be running the injectors at 80% duty cycle which causes some puddling of fuel before the intake opens. How deep can you get with systems like the Holley HP? can you adjust the the integration factor during acceleration? Can you adjust injector timing to suit your cam and engine setup? In a car that accelerates quickly many of these factors are irrelevant, but in a boat that is under extreme load while getting on plane these effects are amplified. Trust me I know, I'm trying to get the bog out of my carb by tweaking the power valve restrictors and tweak the accelerator pumps and jets. Many of us know how to make these adjustments in the analog world. My question is, can we make these adjustments in the digital realm. As I said in the beginning, I have installed an EFI system, but all it allowed me to change was fuel based on load and rpm, ignition timing, and a general enrichment for acceleration. If anyone really wants to know in detail the math behind EFI, I recommend the Mega-Squirt site, I found it to be a tremendous education. It will help you understand the hows and whys so you can get a better tune. As always the discussions on this board are enlightening.
12-13-2011, 09:55 PM
#52
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I've installed an Edelbrock EFI on a SBC and the outcome was amazing. I gained a huge jump in performance and fuel economy over the stock motor. The car never ran so good. When I bought my boat the first thing I looked into was going to EFI. My problem is that I have Lightning wet headers and to add an O2 bung would be difficult and new headers with O2 bungs are about $2500 on top of the $3500 for a complete EFI system it was more than I wanted to get into. I have a few questions though, one system I haven't seen mentioned yet is the ACCEL DFI system. I have a buddy over at Kinsler fuel systems and that was the system they recommended to me. They have a marine rated system that is complete and can support over 650hp which is where I'm at. The other issue I saw was that most electric fuel pumps need to be mounted below the tank so they get a good siphon. On a boat that means placing the pump in the bottom of the bilge. Has anyone had a problem with this? Also what is the consensus on batch mode verses sequential. I've done a little investigating in some of the EFI systems and there is a lot to consider with EFI. You have batch mode and variations thereof and sequential mode. My concern is this, how well do some of these controllers handle things such as the wall wetting effect? Under hard acceleration, a portion of the fuel sticks to the walls of the intake port until air velocity increases with rpm. Some systems, specifically Mega-Squirt actually have a complex algorithm that adjusts fuel flow to adapt to this affect. If this is ignored you will be lean initially and then there will be a rich period until your rpm stabilizes. There is also the issue of injector firing timing, When running at full rpm you may be running the injectors at 80% duty cycle which causes some puddling of fuel before the intake opens. How deep can you get with systems like the Holley HP? can you adjust the the integration factor during acceleration? Can you adjust injector timing to suit your cam and engine setup? In a car that accelerates quickly many of these factors are irrelevant, but in a boat that is under extreme load while getting on plane these effects are amplified. Trust me I know, I'm trying to get the bog out of my carb by tweaking the power valve restrictors and tweak the accelerator pumps and jets. Many of us know how to make these adjustments in the analog world. My question is, can we make these adjustments in the digital realm. As I said in the beginning, I have installed an EFI system, but all it allowed me to change was fuel based on load and rpm, ignition timing, and a general enrichment for acceleration. If anyone really wants to know in detail the math behind EFI, I recommend the Mega-Squirt site, I found it to be a tremendous education. It will help you understand the hows and whys so you can get a better tune. As always the discussions on this board are enlightening.
The fuel pumps survive no problem down low. If you want to raise it you can run a system like Steve suggested or just a high volume low pressure lift pump right into the high pressure pump. Most high pressure pumps like a little pressure on the inlet side. All of this is nothing new, Merc's been running EFI for years and all batch fired except the 496.I mount the fuel pump to the engine just below the balancer. Look on the bottom left. That little pump has no problem supporting 600hp.
Last edited by HaxbySpeed; 12-13-2011 at 10:06 PM.
12-15-2011, 11:06 PM
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Let's not forget the Fast EZ-EFI or the new MSD Atomic EFI:
http://www.atomicefi.com/
http://www.fuelairspark.com/ezefi/default.asp
A few points:
You can go down to any GM dealership and buy a MEFI 4A and harness for about $600. It is one of the best deals in EFI out there. There was also just another large run of MEFI 4B controllers produced, many thousands are available.
If you take the time to look at it closely, this is not true at all, the control algorithms and flexibility of the controller is enormous, and yes, by today's standards. GM controllers and algorithms evolve over time, and the MEFI embodied GM's best thinking at any given time. The MEFI 4's can be run with widebands in closed loop, do 7x, 9x, 24x, 58 trigger wheels, run alternate maps, and much more, it is just of matter of setting it up. Even a MEFI 1 from 1993 can be run in closed loop.
If you read the instructions that come with it, all the important parameters are clearly called out, and there are not that many of them needed to do a very good tune. Trashes post above shows how someone who has never done an EFI system did it in a short amount of time with outstanding results. He read the instructions, was methodical, and cranked it out.
If you have a MEFI or most any other OEM controller you already have very precise barometric correction tables available, no need for different maps.
Actually, salt water does them in the quicker.
Which is exactly why they are not usually implemented in a marine environment. As an example, look closely at the exhaust systems of the newer ski or pleasure boats from 2006 on with O2's and catalyzed systems to see what it takes to keep the O2 sensors from being contaminated. These exhaust systems are nontrivial.
There are a large number of very competent people worldwide who can dial in a MEFI or pretty much any EFI system in short order. Just because they don't post to this forum doesn't mean they aren't out there.
A very good point. All these EFI systems will work relatively well if you take the time to understand how they work and set them up properly, whether is it a Holley, Fast, Accel, Motec, Haltech, AEM, Megasquirt, etc. It really doesn't matter if you have a carburetor, a trained monkey squirting ether into the engine, or the latest EFI system, if the fuel, air, and spark requirements are being met properly at any given instant, the engine does not care. It is the granularity and speed of control that are the differentiating factors.
It mainly comes back to how comfortable a person is setting up a particular system, and if it makes sense economically to do it. Effective laptop computer use is a huge issue for many people when it comes to EFI systems. It rarely makes sense for someone to switch to a completely different system if the current one can be dialed better, whether it be a carburetor or EFI system.
The MEFI or any of the OEM controllers are far more sophisticated than the aftermarket controllers for the most part because of the huge amount of R&D money spent on them and the stringent requirements for production engines. You get to harness this technology for relative pennies. The MEFI and any of the latest OEM controllers, whether it is Delphi, Bosch, Denso, or whoever, are staggeringly complex when you really get deep inside of them. The knock detection and control systems are usually not nearly as advanced in the aftermarket controllers, and the control algorithms for idle control and fault detection and engine protection are way ahead in the OEM controllers. Pop over to the EFILive or HPtuners forum to see how complex the latest Delphi controllers are, and yet there is a huge user community out there tuning them effectively. For the most part, there is not going to be a big red easy button on any of the OEM controllers, and this is by design. I can say with a fair amount of certainty that the car or truck most people use as their daily driver did not get calibrated at the OEM by putting a wideband in it and doing an autotune. Big teams worked on those calibrations for months in painstaking detail. An autotuning system is not bad if it works properly, but even with a good system the maps usually need to be smoothed by hand to put them spot on.
As a brief anecdote, I recently worked on a pair of PSI blown 632's with large cams generating very little vacuum at idle. It formerly had the latest Motec controllers on it and well over $100k was spent on getting everything set up with just the Motec hardware alone. After a year and a half of trying to get this large expensive boat dialed in, with the best people Motec had working on it, this boat would not idle properly or go in an out of gear smoothly, with it being very intractable around the dock or on and off the trailer. The Motec hardware was taken off and MEFI 4B's were put on. I selected a good base calibration for a big blower engine, and on the first engine start on the dyno, it just sat there and idled perfectly. Why? Because the control algorithms for the MEFI, or any of the Delphi controllers are superior. Think about it, how much development time and money has GM and Delphi put into their controllers and algorithms, versus any of the aftermarket controller companies?
For all those throwing their MEFI's in the garbage such as HaxbySpeed suggests, send them to me instead and I will give you money for them!
Bob
http://www.atomicefi.com/
http://www.fuelairspark.com/ezefi/default.asp
A few points:
MEFI 3's and 4's are no longer being produced either.
the MEFI system is a dinosaur.
Anyone who has tuned their own with MEFI burn knows how tedious it can be and how limited the software is if you're not an engineer.
You could make a high elevation map for the lake,
It takes a significant drink of water to kill an O2 sensor. The two things that will kill them the fastest are rich fuel mixtures, and leaded fuel.
The biggest concern with running closed loop for extended periods is as the O2 sensor decay's the tune up will change based on the false data coming from the sensor.
There's probably only two guys in the US, Dustin Whipple and Mark Boos, who have the knowledge and experience to really do a complete tune for a marine engine taking all possible conditions into account.
If you already have a good carb setup it's probably not worth going to TB.
It mainly comes back to how comfortable a person is setting up a particular system, and if it makes sense economically to do it. Effective laptop computer use is a huge issue for many people when it comes to EFI systems. It rarely makes sense for someone to switch to a completely different system if the current one can be dialed better, whether it be a carburetor or EFI system.
The MEFI or any of the OEM controllers are far more sophisticated than the aftermarket controllers for the most part because of the huge amount of R&D money spent on them and the stringent requirements for production engines. You get to harness this technology for relative pennies. The MEFI and any of the latest OEM controllers, whether it is Delphi, Bosch, Denso, or whoever, are staggeringly complex when you really get deep inside of them. The knock detection and control systems are usually not nearly as advanced in the aftermarket controllers, and the control algorithms for idle control and fault detection and engine protection are way ahead in the OEM controllers. Pop over to the EFILive or HPtuners forum to see how complex the latest Delphi controllers are, and yet there is a huge user community out there tuning them effectively. For the most part, there is not going to be a big red easy button on any of the OEM controllers, and this is by design. I can say with a fair amount of certainty that the car or truck most people use as their daily driver did not get calibrated at the OEM by putting a wideband in it and doing an autotune. Big teams worked on those calibrations for months in painstaking detail. An autotuning system is not bad if it works properly, but even with a good system the maps usually need to be smoothed by hand to put them spot on.
As a brief anecdote, I recently worked on a pair of PSI blown 632's with large cams generating very little vacuum at idle. It formerly had the latest Motec controllers on it and well over $100k was spent on getting everything set up with just the Motec hardware alone. After a year and a half of trying to get this large expensive boat dialed in, with the best people Motec had working on it, this boat would not idle properly or go in an out of gear smoothly, with it being very intractable around the dock or on and off the trailer. The Motec hardware was taken off and MEFI 4B's were put on. I selected a good base calibration for a big blower engine, and on the first engine start on the dyno, it just sat there and idled perfectly. Why? Because the control algorithms for the MEFI, or any of the Delphi controllers are superior. Think about it, how much development time and money has GM and Delphi put into their controllers and algorithms, versus any of the aftermarket controller companies?
For all those throwing their MEFI's in the garbage such as HaxbySpeed suggests, send them to me instead and I will give you money for them!
Bob
12-16-2011, 02:36 AM
#54
Not trying to hijack this thread, but I was wondering if you could clarify what exactly PC software is available to the consumer for accessing/tuning on MEFI-5. The products I see let authorized dealers reflash only. I'd like to be able to log on and adust mapping. I've used the OEM software at the engine shop and they will let me borrow it for final tune in the boat, but I'm looking for a long-term solution. Thanks.
12-16-2011, 05:34 AM
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Right back at ya. 
Let's not forget the Fast EZ-EFI or the new MSD Atomic EFI:
http://www.atomicefi.com/
http://www.fuelairspark.com/ezefi/default.asp
Neither of these systems can even be compared to the Holley EFI systems. They have nowhere near the capability or tuning parameters available. I would suggest that you at least investigate a product before trying to discredit it.
A few points:
You can go down to any GM dealership and buy a MEFI 4A and harness for about $600. It is one of the best deals in EFI out there. There was also just another large run of MEFI 4B controllers produced, many thousands are available.
Excellent, do they come with free, easy to use software that will run on any operating system? If not, what does that cost? Do they come with all the sensors needed, a wideband O2 sensor, lots of base calibrations to get you started, optional injector harnesses for EV1 or EV6 injectors, the option to run digital programmable gauges with one wire hook up, can you run dual widebands and set it up to average the two banks or tune off the richest or leanest bank, will it operate a Meth injection system, can it run dual resonant, or non resonant knock sensors and allow you to tune them to your specific engines knock signature, how's the resolution on the fuel and spark maps, can you easily adjust fuel on individual cylinders, does it have lots of programmable inputs and outputs, 2gb of internal datalogging?
MEFI embodied GM's best thinking at any given time.
So for the majority of the Merc guys who are out there running around with MEFI 3's, what time was that?
If you read the instructions that come with it, all the important parameters are clearly called out, and there are not that many of them needed to do a very good tune. Trashes post above shows how someone who has never done an EFI system did it in a short amount of time with outstanding results. He read the instructions, was methodical, and cranked it out.
Just because you can get an engine to run and idle with a MEFI 1 doesn't mean it's anywhere near optimized.. What happens next year if he decides to bolt on a supercharger?
Actually, salt water does them in the quicker.
Which is exactly why they are not usually implemented in a marine environment.
Which is why it's nice to have the option to turn them off and remove them once you're done tuning, which was clearly stated earlier
There are a large number of very competent people worldwide who can dial in a MEFI or pretty much any EFI system in short order. Just because they don't post to this forum doesn't mean they aren't out there.
Perhaps a list for some of the MEFI guy's would be a good resource. I've seen more then a few burnt motors come in tuned by "experts"
All these EFI systems will work relatively well if you take the time to understand how they work and set them up properly, whether is it a Holley, Fast, Accel, Motec, Haltech, AEM, Megasquirt, etc. It really doesn't matter if you have a carburetor, a trained monkey squirting ether into the engine, or the latest EFI system, if the fuel, air, and spark requirements are being met properly at any given instant, the engine does not care. It is the granularity and speed of control that are the differentiating factors.
How many of those have fully potted Coast Guard approved ecm's and systems?
It mainly comes back to how comfortable a person is setting up a particular system, and if it makes sense economically to do it. Effective laptop computer use is a huge issue for many people when it comes to EFI systems. It rarely makes sense for someone to switch to a completely different system if the current one can be dialed better, whether it be a carburetor or EFI system.
Excellent point and one of the biggest benefits to the Holley system. It is incredibly easy to navigate an operate the tuning software.
As a brief anecdote, I recently worked on a pair of PSI blown 632's with large cams generating very little vacuum at idle. It formerly had the latest Motec controllers on it and well over $100k was spent on getting everything set up with just the Motec hardware alone. After a year and a half of trying to get this large expensive boat dialed in, with the best people Motec had working on it, this boat would not idle properly or go in an out of gear smoothly, with it being very intractable around the dock or on and off the trailer. The Motec hardware was taken off and MEFI 4B's were put on. I selected a good base calibration for a big blower engine, and on the first engine start on the dyno, it just sat there and idled perfectly. Why? Because the control algorithms for the MEFI, or any of the Delphi controllers are superior. Think about it, how much development time and money has GM and Delphi put into their controllers and algorithms, versus any of the aftermarket controller companies?
That is ridiculous, I would suggest that maybe the tuners did not understand the PSI blowers, or they weren't really "the best"
For all those throwing their MEFI's in the garbage such as HaxbySpeed suggests, send them to me instead and I will give you money for them!
I will absolutely take you up on this offer, I've got four or five MEFI 4's and a few MEFI 3's. What are you offering?
Bob
http://www.atomicefi.com/
http://www.fuelairspark.com/ezefi/default.asp
Neither of these systems can even be compared to the Holley EFI systems. They have nowhere near the capability or tuning parameters available. I would suggest that you at least investigate a product before trying to discredit it.
A few points:
You can go down to any GM dealership and buy a MEFI 4A and harness for about $600. It is one of the best deals in EFI out there. There was also just another large run of MEFI 4B controllers produced, many thousands are available.
Excellent, do they come with free, easy to use software that will run on any operating system? If not, what does that cost? Do they come with all the sensors needed, a wideband O2 sensor, lots of base calibrations to get you started, optional injector harnesses for EV1 or EV6 injectors, the option to run digital programmable gauges with one wire hook up, can you run dual widebands and set it up to average the two banks or tune off the richest or leanest bank, will it operate a Meth injection system, can it run dual resonant, or non resonant knock sensors and allow you to tune them to your specific engines knock signature, how's the resolution on the fuel and spark maps, can you easily adjust fuel on individual cylinders, does it have lots of programmable inputs and outputs, 2gb of internal datalogging?
MEFI embodied GM's best thinking at any given time.
So for the majority of the Merc guys who are out there running around with MEFI 3's, what time was that?
If you read the instructions that come with it, all the important parameters are clearly called out, and there are not that many of them needed to do a very good tune. Trashes post above shows how someone who has never done an EFI system did it in a short amount of time with outstanding results. He read the instructions, was methodical, and cranked it out.
Just because you can get an engine to run and idle with a MEFI 1 doesn't mean it's anywhere near optimized.. What happens next year if he decides to bolt on a supercharger?
Actually, salt water does them in the quicker.
Which is exactly why they are not usually implemented in a marine environment.
Which is why it's nice to have the option to turn them off and remove them once you're done tuning, which was clearly stated earlier
There are a large number of very competent people worldwide who can dial in a MEFI or pretty much any EFI system in short order. Just because they don't post to this forum doesn't mean they aren't out there.
Perhaps a list for some of the MEFI guy's would be a good resource. I've seen more then a few burnt motors come in tuned by "experts"
All these EFI systems will work relatively well if you take the time to understand how they work and set them up properly, whether is it a Holley, Fast, Accel, Motec, Haltech, AEM, Megasquirt, etc. It really doesn't matter if you have a carburetor, a trained monkey squirting ether into the engine, or the latest EFI system, if the fuel, air, and spark requirements are being met properly at any given instant, the engine does not care. It is the granularity and speed of control that are the differentiating factors.
How many of those have fully potted Coast Guard approved ecm's and systems?
It mainly comes back to how comfortable a person is setting up a particular system, and if it makes sense economically to do it. Effective laptop computer use is a huge issue for many people when it comes to EFI systems. It rarely makes sense for someone to switch to a completely different system if the current one can be dialed better, whether it be a carburetor or EFI system.
Excellent point and one of the biggest benefits to the Holley system. It is incredibly easy to navigate an operate the tuning software.
As a brief anecdote, I recently worked on a pair of PSI blown 632's with large cams generating very little vacuum at idle. It formerly had the latest Motec controllers on it and well over $100k was spent on getting everything set up with just the Motec hardware alone. After a year and a half of trying to get this large expensive boat dialed in, with the best people Motec had working on it, this boat would not idle properly or go in an out of gear smoothly, with it being very intractable around the dock or on and off the trailer. The Motec hardware was taken off and MEFI 4B's were put on. I selected a good base calibration for a big blower engine, and on the first engine start on the dyno, it just sat there and idled perfectly. Why? Because the control algorithms for the MEFI, or any of the Delphi controllers are superior. Think about it, how much development time and money has GM and Delphi put into their controllers and algorithms, versus any of the aftermarket controller companies?
That is ridiculous, I would suggest that maybe the tuners did not understand the PSI blowers, or they weren't really "the best"
For all those throwing their MEFI's in the garbage such as HaxbySpeed suggests, send them to me instead and I will give you money for them!
I will absolutely take you up on this offer, I've got four or five MEFI 4's and a few MEFI 3's. What are you offering?
Bob
12-16-2011, 06:04 AM
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Here's a MEFI 3 fuel map.. You have to tune the various maps and then make sure you match the lines that they share between them. What happens if you want to tune past 6000rpm on this one?
Lets review the MEFI tuning process. You've got one guy driving the boat, one guy laying on the floor at 80+ mph with a laptop and a separate wideband controller watching Air fuel and MAP. Then you stop, download the calibration from your MEFI, open tuner pro, select the proper xdf, load the downloaded cal, make some changes, upload the file back into the MEFI which is sloooow, start the boat, run it again trying to duplicate the previous conditions so you know the changes you made were good, and repeat.. Oh ya, does the standalone wideband controller come with the "best EFI deal out there"
Lets review the MEFI tuning process. You've got one guy driving the boat, one guy laying on the floor at 80+ mph with a laptop and a separate wideband controller watching Air fuel and MAP. Then you stop, download the calibration from your MEFI, open tuner pro, select the proper xdf, load the downloaded cal, make some changes, upload the file back into the MEFI which is sloooow, start the boat, run it again trying to duplicate the previous conditions so you know the changes you made were good, and repeat.. Oh ya, does the standalone wideband controller come with the "best EFI deal out there"
12-16-2011, 06:19 AM
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Here's a Holley fuel Map. If you want to make quick changes you can shrink it and it will tune several cells at once and the software will automatically smooth it after. If you want more RPM you can change it easily. If you want to go 2,3,4,5 Bar, you can change it easily. Another thing I like is the table is in lbs/hr. I think this is much easier to grasp then BPW of x injector at x pressure = y amount of fuel.
12-16-2011, 01:11 PM
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I think you are missing the point, I am not bashing or discrediting any of these systems. The Holley is a fine system, as is the Fast, MSD, Motec, etc. For the most part they have nice software interfaces, especially the newer ones, that are relatively easy to understand and the controllers offer nice features. If you like the new Holley system and are comfortable with it, great, and it is helpful that you point out the good features of the system. All of these EFI systems have their strengths and weaknesses, and if you can make any of them work effectively on a particular setup, fantastic.
If you look at where Fast, Motec, Accel, etc. were 5 or 10 or 15 years ago, and compare it to the MEFI and OEM systems of the time, the OEM systems are technically superior. Look at a snapshot in time right now and see what the OEM's are doing with direct injection and torque based management models in their ECM's. I believe you will find that it is pretty far ahead of what the aftermarket companies are offering. If you can harness that technology and wield it effectively on a project, that is a pretty nice thing. I enjoy helping people who contact me and you can call me anytime and I'll be glad to answer questions.
If you look at where Fast, Motec, Accel, etc. were 5 or 10 or 15 years ago, and compare it to the MEFI and OEM systems of the time, the OEM systems are technically superior. Look at a snapshot in time right now and see what the OEM's are doing with direct injection and torque based management models in their ECM's. I believe you will find that it is pretty far ahead of what the aftermarket companies are offering. If you can harness that technology and wield it effectively on a project, that is a pretty nice thing. I enjoy helping people who contact me and you can call me anytime and I'll be glad to answer questions.
