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Looking for best EFI system for lycoming 540

I am stepping into an unknown area here. I have an injected 540 but looking to step that up and get better performance and control. I am not an engine guy so looking for input to make my 540 fly the best. Thanks to all that can give feedback
 
I had sds ignition in my rocket and loved it. You will want some help installing the magnets. I ran one mag to keep my system simple. If you go with the full efii you will have to completely redesign your electrical system to provide redundancy. Going with CPI and one mag you get 90% of the benefit.
 
+1 for EFII

I am in phase 1 testing and I couldn't be happier with the EFII system...

...and the customer service.
 
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I am stepping into an unknown area here. I have an injected 540 but looking to step that up and get better performance and control. I am not an engine guy so looking for input to make my 540 fly the best.

Jeff, it may be best to start by realizing what EFI will or will not do for your RV-10. Is there a particular area of operation in which you would like better performance and control?
 
Another SDS user here. Absolutely love mine. As far as SDS vs EFII, do some searches and go with who makes you more comfortable.
 
We're plumbing more SDS systems than EFii right now--have a couple in beta test. If you hadnt previously planned for a duplex system--especially in the cabin and tanks---then you need to STOP and think about how all of this works together.

Tom
 
Jeff, it may be best to start by realizing what EFI will or will not do for your RV-10. Is there a particular area of operation in which you would like better performance and control?

...and this is THE issue here. What exactly is the OP trying to get out of the system? "better" performance is a very broad term, and this happens to be one area where the vendors of the two systems will tell a prospective customer a different tale.

Talk to both guys - Then make your decision.
 
Cracks me up...

The "best" system is the one that respondent purchased...

I can say that my Barrett IO-540 with EFII starts like a car, every time, hot or cold. Programming is very easy, and is done on the fly. The engine runs very smooth and though I am still in testing, the EGT spread is within about 8 degrees across six cylinders.

Do your own research, talk to people that run the different systems, and make your choice; it will likely turn out fine either way.

Sounds like Ford's and Chevys with a few Dodges thrown in...:D
 
The engine runs very smooth and though I am still in testing, the EGT spread is within about 8 degrees across six cylinders.

You do realize temperature spread has nothing to do with GAMI spread? The goal is to see them all peak at the same time, regardless of their individual indicated temperatures.
 
Now, now... Back to the original topic, again.

I am stepping into an unknown area here. I have an injected 540 but looking to step that up and get better performance and control. I am not an engine guy so looking for input to make my 540 fly the best. Thanks to all that can give feedback

Jt rotor guy - can you describe the shortfalls in your current FI system you want to improve on, & what performance/operational improvements you would like to see by changing it out for a EFI system?
If you list them, we can reply with our experiences and results, objectively (wishfull thinking on my part...)
 
...and this is THE issue here. What exactly is the OP trying to get out of the system? "better" performance is a very broad term, and this happens to be one area where the vendors of the two systems will tell a prospective customer a different tale.

Talk to both guys - Then make your decision.

I've talked to both, but missed this... I think.... what are you hinting at?

The vibe I got was this:

SDS seemed super programmable and can do whatever you want. The platform had a lot of clever CNC machined parts to fit whatever needs you have.

EFII seemed more install and forget. More time seems to have been spent on polishing the interface and install than providing flexibility.

As for better performance, I don't think any EFI system is going to produce more HP in our application, and better economy really boils down to LOP.

When I talked to both vendors SDS couldn't do individual injector trim on a 6cyl engine because the EM-5 only has 4 injector drivers, so they get around that by using two EM-5s with one driving 3 injectors and the other driving the other three. Should one EM-5 fail, then we go back to batch firing.

EFII could do individual injector trim, but it didn't sound like anybody really does and that LOP tuning wasn't as much of a thing.

Another difference was the failover. The SDS functionally uses a relay to assign which EM-5 is driving the injector so that it fails mechanically to the seconary EM-5, while EFII seems to have a FET on the injector output then wires both CPUs to the injector and then only has one active at a time.

At the end of the day I don't trust an open loop EFI system to lean my airplane, so that means knob and EGT/CHT gauges. At that point I wanted to avoid the additional fuel system complexity, and just called up Don and bought a FM-150.

For me, I think the only thing that EFI buys you is the ability to run pretty much any fuel as it doesn't appear to buy you any additional HP or economy.

schu
 
EFII

The bottom line is: No one ever goes back to the old engine systems once they experience how much better these engines run with modern engine management. The engines start better, run smoother, are more efficient and make more HP.

A good comparison is how a 1960 car runs vs a new car.

As far as supplier options- do your homework, your answer will be clear.

Robert
EFII
 
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The bottom line is: No one ever goes back to the old engine systems once they experience how much better these engines run with modern engine management. The engines start better, run smoother, are more efficient and make more HP.

Robert
EFII

I would be very interested in some data to support this statement. I’ve seen the claims by EFII and SDS on more power and higher efficiency, but have not seen supporting data for these claims - such as on the EFII website “Up to 10% more power”.

Perhaps these claim have a base of standard mags for comparison? Are the claims based on tuning one-off race engines or for the 99.9% of us flying behind a standard Lycoming?

Specifically, if there is data to show more power and/or higher efficiency on a standard Lycoming engine running traditional fuel injection, with balanced injector nozzles and electronic ignition (like dual pMags), please provide.

Call
 
EFII

Carl,
You can get endless reports here from people who have run traditional systems as well as EFII on the same engine - this is your best comparison data. The vast majority of this group will tell you how much better their engine runs with EFII at all operating points.

We are closing in on 700 installations now, there is no going back for those of us who have experienced the benefits of a modern Lyc engine.

The biggest challenge of mechanical injection is achieving fuel balance between the cylinders - there is no positive control of the fuel distribution like there is with electronic injection. You can try to balance mechanical injection at one operating point with precision injectors. But the balance will fall apart at every other operating point. And it's really bad at low spider pressures such as during engine starting (hello hot start).

If you want the most out of your engine - there isn't much question of what will give you that result.

Robert
EFII
 
I've talked to both, but missed this... I think.... what are you hinting at?

The vibe I got was this:

SDS seemed super programmable and can do whatever you want. The platform had a lot of clever CNC machined parts to fit whatever needs you have.

As for better performance, I don't think any EFI system is going to produce more HP in our application, and better economy really boils down to LOP.

When I talked to both vendors SDS couldn't do individual injector trim on a 6cyl engine because the EM-5 only has 4 injector drivers, so they get around that by using two EM-5s with one driving 3 injectors and the other driving the other three. Should one EM-5 fail, then we go back to batch firing.

Another difference was the failover. The SDS functionally uses a relay to assign which EM-5 is driving the injector so that it fails mechanically to the secondary EM-5.

At the end of the day I don't trust an open loop EFI system to lean my airplane, so that means knob and EGT/CHT gauges.

For me, I think the only thing that EFI buys you is the ability to run pretty much any fuel as it doesn't appear to buy you any additional HP or economy.

schu

SDS was the first to introduce individual cylinder fuel trim in this market back in Jan. 2016. Over 90% of our Lycoming customers opt for dual ECUs these days. In order to have a mix of redundancy and features we use both ECUs on 6 cylinder systems to control both fuel and spark. Our systems are all batch fired at all times.

Either ECU can drive all the injectors in the event of failure of one ECU. The main goal is to get you safely down if that happens.

Cruise leaning is usually accomplished with the LOP button (another first by SDS) which simultaneously leans the % programmed in and advances timing the amount programmed in. Works very slick as you can see in our RV-10 videos. Since the engine is sitting at a constant power setting, AFR remains pretty static as well and we're ultimately using EGT to determine how much LOP to run, just like with mechanical injection. Closed loop wouldn't do much for you in cruise.

We typically see around a 2-3% gain in power over mechanical injection from dyno tests on similar engines. Fuel economy seems similar to mechanical FI but is hard to compare on different airplanes with different props, induction and exhaust systems. Baseline RV-10- 174 KTAS @ 17,000 feet on 10 GPH with an MT 3 blade prop.

Dave Anders has seen some incredible economy up at these altitudes and low rpm where the mechanical injection can't meter very accurately. Admittedly most folks don't fly like that.

No more hot start and lumpy idle issues with SDS. Many people buy for this reason alone.

In the end, it's a personal preference and comfort thing. Certainly mechanical FI does it for many folks but we've never been busier on the aircraft side with order backlogs approaching 30 days as of today. Lots of people are choosing SDS EFI over legacy fuel metering and mags. We have several customers with over 2000 flight hours each on our EFI now and over 750,000 flight hours collectively on over 2100 systems.
 
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Robert, when can we expect a user operating manual?

https://www.flyefii.com/downloads/

A good comparison is how a 1960 car runs vs a new car.

System 32 is a speed-density system, the operating principle delivered in a 67 VW Type 3 as a Bosch D-Jetronic. The primary inputs are just RPM, manifold pressure, and air temperature. Nothing wrong with the concept (KIS is good), but claiming it's anything like current automotive practice is, ummm...unrealistic.

It would be fair to say the electronics are far more reliable, even if they do drive an elementary 1960's operating scheme. The semiconductor industry has come a long way in 50 years.
 
types of fuel injection

Some cars use speed density electronic injection, some use mass air.
We use speed density since it's more reliable. Mass air sensors can easily drift, or fail.

The semi-sequential, risc processor based System32 EFII is quite modern and really makes these engines run well (as our customers are well aware).

Robert
EFII
 
I am stepping into an unknown area here. I have an injected 540 but looking to step that up and get better performance and control. I am not an engine guy so looking for input to make my 540 fly the best. Thanks to all that can give feedback

If you're not an engine guy and don't plan on installing and tweaking this yourself (and enjoy that kinda thing) then I would suggest you just stick with the standard FI/Ign system. Quite a big install package between plumbing and backup electrical system so it's not a easy job.

Maybe a single EI and tuned injectors will get you 95% of what you are looking for. IMO not sure the complexity is worth the touted advantages.

And being that no one (other than a select few) will know anything about your 'new' system if you have trouble you're pretty much on your own.

Me personally, I won't install or work on anything with a FADEC type system.
 
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If you're not an engine guy and don't plan on installing and tweaking this yourself (and enjoy that kinda thing) then I would suggest you just stick with the standard FI/Ign system. Quite a big install package between plumbing and backup electrical system so it's not a easy job.

Maybe a single EI and tuned injectors will get you 95% of what you are looking for. IMO not sure the complexity is worth the touted advantages.

And being that no one (other than a select few) will know anything about your 'new' system if you have trouble you're pretty much on your own.

Me personally, I won't install or work on anything with a FADEC type system.

similar feelings here. I have installed custom EFII systems in auto applications and love them. However, when I built the 540 for the 10, I chose mech FI and dual EI. I simply couldn't see how EFII could improve efficiency beyond a percent or two (I do custom tune nozzle size and work my red knob in all phases of flight) over mech FI. I only saw advantages in areas like hot start, no vapor lock, etc. To me, it wasn't worth the cost and risks, due to electrical dependency.

In my case, I had a custom built EI setup, so low cost. I suppose if looking at a couple of Pmags, the cost delta is not as great for others.

Larry
 
Isn't it Great?

Having multiple choices to achieve the same, or very similar results. Just as there are a LOT of choices of cars/trucks to choose from just to get from point A to B, when just one would accomplish the task.
We look at the options, and for whatever reason that is "best" for us, we choose the product. Once we've got it, we find that it's "The best thing since sliced bread." or it's not and we rip it out and get something else.
Thus, the experimental world is more fun than the certificated.
Therefore: Read as much information on the various systems available. IF possible, talk to owners of each to get their perspective - while hopefully being able to filter out the competitor's "noise" until you are ready to listen to and research their product. Then, make your buying decision and see how it goes from their.
 
Having multiple choices to achieve the same, or very similar results. Just as there are a LOT of choices of cars/trucks to choose from just to get from point A to B, when just one would accomplish the task.
We look at the options, and for whatever reason that is "best" for us, we choose the product. Once we've got it, we find that it's "The best thing since sliced bread." or it's not and we rip it out and get something else.
Thus, the experimental world is more fun than the certificated.
Therefore: Read as much information on the various systems available. IF possible, talk to owners of each to get their perspective - while hopefully being able to filter out the competitor's "noise" until you are ready to listen to and research their product. Then, make your buying decision and see how it goes from their.

Agree and very sound advice. Exactly what we recommend. :)
 
This thread is a perfect summary of what I experienced talking to both vendors. Specifically:


rv6ejguy said:
Cruise leaning is usually accomplished with the LOP button (another first by SDS) which simultaneously leans the % programmed in and advances timing the amount programmed in. Works very slick as you can see in our RV-10 videos. Since the engine is sitting at a constant power setting, AFR remains pretty static as well and we're ultimately using EGT to determine how much LOP to run, just like with mechanical injection. Closed loop wouldn't do much for you in cruise.

We typically see around a 2-3% gain in power over mechanical injection from dyno tests on similar engines. Fuel economy seems similar to mechanical FI but is hard to compare on different airplanes with different props, induction and exhaust systems. Baseline RV-10- 174 KTAS @ 17,000 feet on 10 GPH with an MT 3 blade prop.

Compared to:

rcpaisley said:
The bottom line is: No one ever goes back to the old engine systems once they experience how much better these engines run with modern engine management. The engines start better, run smoother, are more efficient and make more HP.

A good comparison is how a 1960 car runs vs a new car.

You can get endless reports here from people who have run traditional systems as well as EFII on the same engine - this is your best comparison data. The vast majority of this group will tell you how much better their engine runs with EFII at all operating points.

We are closing in on 700 installations now, there is no going back for those of us who have experienced the benefits of a modern Lyc engine.


If I was buying a system I know for sure who I would be working with.

That said, I decided on AFP due to a few factors:

1. I didn't want something that couldn't be worked on in AK where I like to fly.

2. I have a high wing airplane and didn't want to deal with a header tank.

3. Resale for bush craft is probably better with nothing that requires electrical power.

4. I figured I could get 80% there with one mag and one EI.

So, I have a spot in my panel for a EI unit, but will hold off until after first flight since I already have mags.
 
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I think it's fair to say that EFI isn't the right choice for everyone and every mission, it's just another choice.

Lots of folks want one EI but prefer to retain a mag and I understand why and respect that. Happy to supply one EI in those cases. There are certainly some advantages to having that one mag there.

When making these choices, weigh the pros and cons, cost, serviceability, advantages, disadvantages, tech support, customer service etc.

What's right for Jack may not be the best for Peter. We're happy to discuss all these things with people who may be thinking of EI or EFI and I'll give you a straight answer without the sales pitch. I've talked a few out of electronic engine controls over the years as I didn't think it would be the best choice for their typical mission.
 
Some cars use speed density electronic injection, some use mass air.

Roughly 50% of the current new car fleet has gone to direct injection, not the port injection discussed here. All operate in closed loop after warmup, most using multiple O2 sensor feedback. All vary ignition timing in concert with mixture change in response to power request, usually while exchanging information with the transmission.

Put another way, a system "like a new car" would run lead free fuel in closed loop and incorporate propeller control...one cockpit handle, always running at minimum fuel flow for the power requested. I understand System 32 has expansion potential, so maybe someday. Until then, it's a relatively simple 1960's control scheme with modern electronics. That's fine (again KIS is good, particularly in the EAB world), but let's educate, not confuse.

The semi-sequential, risc processor based System32 EFII is quite modern and really makes these engines run well (as our customers are well aware).

Reduced Instruction Set Computer processor. I'm not a computer person. Isn't a Raspberry Pi an RISC?

EFI advantages at this level don't have anything to do with the processor. They are various functions of the pintle injector and high pressure fuel. Let's discuss "semi-sequential". I'll bet readers would like to know what the term means.
 
. . . . a speed-density system, the operating principle delivered in a 67 VW Type 3 as a Bosch D-Jetronic. The primary inputs are just RPM, manifold pressure, and air temperature. Nothing wrong with the concept (KIS is good), but claiming it's anything like current automotive practice is, ummm...unrealistic.

It would be fair to say the electronics are far more reliable, even if they do drive an elementary 1960's operating scheme. The semiconductor industry has come a long way in 50 years.

That thing was terrible. It had points to fire the injectors the sensors and connectors were unreliable. I worked on hundreds of these. You could tell the really problem units - the back bumper had lots of scratches where the mechanic put his foot to scratch his thinker . . . 500ms delay from throttle to response. It was really just a poor implementation of the theory in general, but speed-density systems really operate on an assumption that the volumetric efficiency (thus airflow) remains unchanged in the engines life.

S-D is always going to be less responsive in its pure form. Pretty irrelevant for aviation though.

OT but I would be for direct injection with stratified charge to reduce detonation tendency, allow increased Cr, and yield higher BMEP and efficiency.
 
My new Colorado truck has direct injection - has a compression ratio of 11.5 to 1 and burns 87 octane unleaded.

Now if someone can do direct injection for a Lycoming, I’d buy it.

Carl
 
This thread is a perfect summary of what I experienced talking to both vendors. Specifically:

If I was buying a system I know for sure who I would be working with.

That said, I decided on AFP due to a few factors:

1. I didn't want something that couldn't be worked on in AK where I like to fly.

2. I have a high wing airplane and didn't want to deal with a header tank.

3. Resale for bush craft is probably better with nothing that requires electrical power.

4. I figured I could get 80% there with one mag and one EI.

So, I have a spot in my panel for a EI unit, but will hold off until after first flight since I already have mags.

So in this instance, I can see why the benefits of EFI do not outweigh the liabilities for you. My primary reason for switching to EFI does not even register on your radar, for example. We have different mission requirements, and there’s nothing wrong with that.

I am curious about the need for a “header tank” on your airplane (I’m guessing a Bearhawk). A duplex valve should still route fuel to each tank in your system, and the return pressure sure will get it pushed uphill. Can you expand on the header tank requirement?
 
The semi-sequential, risc processor based System32 EFII is quite modern and really makes these engines run well (as our customers are well aware).

Robert
EFII

RISC was developed in the 70's. I remember learning about it like it was "the new thing" while I was in Junior high school in the early 80's. The whole point of RISC was to allow more processing power out of the available slow processors. Calling it modern tech is not just a stretch, it's beyond a stretch.
 
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Reduced Instruction Set Computer processor. I'm not a computer person. Isn't a Raspberry Pi an RISC?

EFI advantages at this level don't have anything to do with the processor. They are various functions of the pintle injector and high pressure fuel. Let's discuss "semi-sequential". I'll bet readers would like to know what the term means.

I am a computer person. One that writes/compiles software as well as maintains my own personal linux distro.

RISC is basically a concept of how to optimize CPU instructions by making them uniform, and yes the ARM architecture (the specific instruction set) found on a Raspberry Pi is RISC based.

Pretty much all this means is that Robert is using an ARM chip instead of the 68HC12 cpu.

Why would that matter? Well, from the perspective of building a graphical interface, or interacting with other systems like disks or networks, a lot. In the case of firing an injector, not really that much because you are working through your instructions 25,000,000 times a second, and firing 4 injectors 45 times a second. That leaves plenty enough time left over to sample the mixture knob, the OAT sensor, the pressure sensor, the throttle position, the crank position, etc. A real time OS doesn't schedule or queue a task like your PC, if there is enough time to do everything that needs to be done, then there really isn't any advantage to having more time left over.

All of that said, I do think that the EM-5 is due for an update and I suspect Ross would agree with me. Having more injector channels and more cycles will allow you to add features, but it's the features and channels that make it better than the predecessor, not the CPU architecture.

I suspect that when the EM-6 is released it will be like the CPI-1 and CPI-2. The CPI-1 works just fine and they are still sold, but the CPI-2 has more features and is a newer generation. Take your pick.

In regards to EFII and SDS:

I find Ross balanced with transparent and technical information regarding both with the pros and cons, the limitations and the advantages.

Robert is running a more modern CPU, and the graphical interface is certainly nicer in the panel, but then I run into stuff like this:

"Dual 32 bit RISC processors provide modern 3D mapping of ignition and fuel functions to allow your engine to run with greater efficiency, easier starting, and more maximum power."

and

"Up to 10% increase in available horsepower."

and

"Decreased weight – no magnetos or mechanical fuel pump."

And I wonder what about the 32bit ARM architecture has anything to do with efficiency? Does a faster computer fire my injectors.... faster? I hope not! I don't buy a ford over a chevy because of what CPU is in it, I trust either will fire the injectors at the speeds the engine turns at. Features are what matter.

As for 10% increase in HP... well, if we are talking leaner mixtures or more timing, sure, but that can be done with the red knob and EI. If we are talking about 10% more just because of better atomization and fuel distribution, then I really have my doubts.

Decreased weight due to no mags or mech fuel pump? Right.... Well, I'm going to need an additional electric pump, so that's a wash, I omit mags, but then I have coils, duplex fuel valve, return fuel plumbing, pressure regulator, injectors, and CPU bricks. Notice I haven't said a word about additional batteries or alternators, which you would be wise to install.
 
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I am curious about the need for a “header tank” on your airplane (I’m guessing a Bearhawk). A duplex valve should still route fuel to each tank in your system, and the return pressure sure will get it pushed uphill. Can you expand on the header tank requirement?

Yup, bearhawk, and I'm happy to explain.

The problem is that pumps would go down in the fuse and you end up with gravity feeding them as you don't want pumps sucking.

The rub is when you have two fuel pumps running and the engine is at idle. In this situation you are drawing a lot of fuel and pushing it through your regulator back into the tanks. Depending on the pumps and other factors, you could be moving more than 50GPH through the system.

Given the bearhawk only calls out for 3/8 fuel lines, and has a front and rear pickup, you could certainly find yourself in a situation where the pump is pulling harder than gravity feeds it, and if you are low on fuel, and at idle, then unport a pickup, the pump will almost certainly pull air into the system.

A header tank more or less fixes this and it's common on big injected continental powered airplanes like the 185. Another way to fix it is to put the pumps in the wing roots, but then you pretty much need to make the pump the valve as you wouldn't want to select the left tank with the right pump on, and pump failure could cause you to loose a lot of fuel depending on how awesome you are at balancing.

Another factor for a high wing is that some people really really really want a both setting, but that's not ideal with a duplex valve, but if you have a big enough header tank you can return fuel to it and retain the both. Also, where the factory puts the fuel selector valve doesn't have a lot of room for duplex valve.


I'm doing things a little different. I installed 1/2" lines down the doors to an andair duplex valve with 1/8 vapor return lines (FS22), to the boost pump, to the mechanical pump, to a Tee with .020 bleeder back to valve, with the main line going to a FM-150.

My plan is to bleed 6-8GPH through the shrowded and cooled mechanical pump back to the tank to cool it further and also to give vapor a place to go. This more or less mirrors the continental injection system which can run mogas. The up-sizing of the fuel lines to 1/2 will for sure give me that much additional volume. If everything goes to plan, I should be able to run mogas with the additional cooling. If it doesn't, then I'll remove the tee, cap off the 1/8 return lines, and have a standard AFP install.

clear as mud?
 
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I find Ross balanced with transparent and technical information regarding both with the pros and cons, the limitations and the advantages.

Robert is running a more modern CPU, and the graphical interface is certainly nicer in the panel, but then I run into stuff like this:

And that's the same thing I ran into, and why I went with Ross's system. I'm an engineer by trade with degrees in physics and chemistry. When I was researching these systems for my plane and asked the same questions to both Ross and Robert, I got facts and data (with references) from Ross, and I got glossy marketing from Robert. Glossy marketing doesn't do me much good.

Both systems will mostly do what I want - but I liked the background and no-BS approach that Ross gave, with actual TECH support (as in TECHNICAL - the key part) for the questions I had. I was installing a computer to run my engine, and I wanted to talk to a computer guy that built it, not a salesman trying to push it.
 
The rub is when you have two fuel pumps running and the engine is at idle. In this situation you are drawing a lot of fuel and pushing it through your regulator back into the tanks. Depending on the pumps and other factors, you could be moving more than 50GPH through the system.

So, why would you run both pumps at idle??

I have two pumps in the SDS system, will use both for take off/landing. Otherwise only one pump at a time.
 
So, why would you run both pumps at idle??

I have two pumps in the SDS system, will use both for take off/landing. Otherwise only one pump at a time.

Coming in for a landing, you will probably have both pumps on, you might be low on fuel, and the engine will be at idle, meaning it's not consuming much fuel. Result = a lot of fuel cycling through the system with the highest chance of unporting a tank.
 
Electronic direct injection so far hasn't proven to be as durable as port injection. Quite a number of early issues with HP pumps and injectors.

Another issue is carboning up of the back sides of intake valves across almost all OEM brands except those copying Toyota/ Lexus where BOTH systems are fitted to many of their engines.

When its working, DI is magic as far as suppressing detonation and allowing higher CRs for better thermal efficiency and power. We see 10 to 10.5 CRs on turbo engines running 87 octane and up to 14 to 1 naturally aspirated these days on some Atkinson cycle engines from Toyota and Mazda, allowing TEs to match or exceed light diesels in some cases.

Unless we remove one spark plug from our Lycomings or cast some new heads, we won't be seeing DI any time soon fitted to them.

With regards to the header tank idea, we have a number of shoulder and high wing aircraft using this setup with good results. Return to the header, gravity feed from tanks to header with decent sized lines. Can save having the Duplex valve.

Yes, on the microprocessor front, a Lycoming turning at 2700 rpm doesn't challenge a 68HC much. Lots of time to execute the compact code to make the fuel and spark happen on time. We stick with the proven and familiar here as you don't need any more. They work fine on bike stuff turning 5X this rpm.

Weight wise, we see deltas of -2 to 0 pounds, depending on mag and carb/ servo type. Nothing huge either way.
 
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"Dual 32 bit RISC processors provide modern 3D mapping of ignition and fuel functions to allow your engine to run with greater efficiency, easier starting, and more maximum power."

3D ignition mapping is a standard function of the AutoSport Labs ignition controllers I use with EDIS modules. The controllers are currently $199. I've never found a use for it, but it's there. In fairness, it does require plugging in a laptop, as there is no panel display.

Is the Fly EFii 3D also just a graphical presentation?
-
 

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All the talk about sequential (can't do on a Lyc. without a cam sensor) semi-sequential, or batch fire strategies, or processor types matters little here. MoTec uses MULTIPLE cores and very complex code to look at crank angle vs. MAP for instance, but makes the same power as SDS on the same engine, same dyno, one of our dealers found.

On a Lyc. boring along in cruise at X MAP and X RPM, all that matters is that each cylinder receives the right amount of fuel for the amount of air that cylinder is flowing and that the spark timing occurs at the optimal time.

Same goes for an 800hp Sport class engine at Reno.

This is exactly why in cruise, we don't see big gains in fuel economy with EFI over well set up mechanical injection in most cases running at typical cruise MAP and rpms.

Of much more importance on how an engine runs and responds is injector orientation and placement near the port. Comparing how X ECU runs vs. Y ECU would require changing only one variable- ie both using the same injector and placement and just changing the ECU. When one system had a poorly orientated injector and you change the ECU AND injector orientation, you can't tell which variable resulted in better running. The scientific method should be employed when comparing most changes on aircraft and engines if you want to really learn.
 
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All the talk about sequential (can't do on a Lyc. without a cam sensor) semi-sequential, or batch fire strategies, or processor types matters little here.

Still, I'm pretty sure readers would like to hear Robert's explanation of semi-sequential injection...the when, where, and how long it actually injects fuel.

I've attached a quick sketch to make it easier. Robert, perhaps you could add to it in order to illustrate the injector open periods?
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I find it interesting that a respected member of this community is attempting to inflict a death by 1000 cuts upon a paying vendor of Doug's site.
 
I find it interesting that a respected member of this community is attempting to inflict a death by 1000 cuts upon a paying vendor of Doug's site.

I don’t get it. Are you talking about Dan? If so, asking for data to back claims is hardly death by 1000 cuts, unless those claims are baseless. Besides, asking for and operating on the data is what Dan does, and why he is respected.

I really appreciated the work he did around anonymous mode GDL-82, and other work around an air box that doesn’t suck.
 
I find it interesting that a respected member of this community is attempting to inflict a death by 1000 cuts upon a paying vendor of Doug's site.

The poster made claims that semi-sequential injection is better. I also would like to understand the rationale for that claim, as I also question it. Also would like to know what he means by it, as the industry only refers to batch or sequential injector firing; Never heard of semi-sequential prior to this post. Nothing wrong with calling out a vendor to back up his claims, advertiser or not. I personally appreciate those that ask for backup details on claims of improvement.

From my experience, proper sequential injector firing is not possible without a cam position sensor.

Larry
 
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Danger! Danger!

This conversation has gone down the same path as the previous one did on this topic...

...and the result is the same.

Maybe it's time to close it down...
 
This conversation has gone down the same path as the previous one did on this topic...

...and the result is the same.

Maybe it's time to close it down...

Or perhaps it's simply time to get answers to the questions? Or do we just close down threads one after another to avoid have a fact-based discussion in favor of marketing?
 
This conversation has gone down the same path as the previous one did on this topic...

...and the result is the same.

Maybe it's time to close it down...

Or possible to leave it open so that it can be quality fodder for those making decisions on which EFII vendor to choose. I see significant differences in the two vendors responses to these issues and feel that can help many people in choosing one or the other.
 
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