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  #21  
Old 02-22-2021, 06:06 PM
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rv6ejguy rv6ejguy is offline
 
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Quote:
Originally Posted by akschu View Post
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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Ross Farnham, Calgary, Alberta
Turbo Subaru EJ22, SDS EFI, Marcotte M-300, IVO, Shorai- RV6A C-GVZX flying from CYBW since 2003- 445.9 hrs. on the Hobbs,
RV10 95% built- Sold 2016
http://www.sdsefi.com/aircraft.html
https://www.youtube.com/channel/UCiy...g2GvQfelECCGoQ



Last edited by rv6ejguy : 02-23-2021 at 08:05 AM.
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  #22  
Old 02-22-2021, 06:37 PM
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DanH DanH is offline
 
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Robert, when can we expect a user operating manual?

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

Quote:
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.
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  #23  
Old 02-22-2021, 07:11 PM
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rcpaisley rcpaisley is offline
 
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Default 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
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  #24  
Old 02-23-2021, 07:46 AM
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Walt Walt is offline
 
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Quote:
Originally Posted by Jt rotor guy View Post
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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EXP Aircraft Services LLC
Specializing in RV Condition Inspections, Maintenance, Avionics Upgrades
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Last edited by Walt : 02-23-2021 at 08:02 AM.
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  #25  
Old 02-23-2021, 08:28 AM
lr172 lr172 is offline
 
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Quote:
Originally Posted by Walt View Post
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
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  #26  
Old 02-23-2021, 09:19 AM
622BH 622BH is offline
 
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Default 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.
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  #27  
Old 02-23-2021, 09:59 AM
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rv6ejguy rv6ejguy is offline
 
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Quote:
Originally Posted by 622BH View Post
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.
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Ross Farnham, Calgary, Alberta
Turbo Subaru EJ22, SDS EFI, Marcotte M-300, IVO, Shorai- RV6A C-GVZX flying from CYBW since 2003- 445.9 hrs. on the Hobbs,
RV10 95% built- Sold 2016
http://www.sdsefi.com/aircraft.html
https://www.youtube.com/channel/UCiy...g2GvQfelECCGoQ


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  #28  
Old 02-23-2021, 02:38 PM
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akschu akschu is offline
 
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This thread is a perfect summary of what I experienced talking to both vendors. Specifically:


Quote:
Originally Posted by rv6ejguy
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:

Quote:
Originally Posted by rcpaisley
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.

Last edited by akschu : 02-23-2021 at 11:51 PM.
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  #29  
Old 02-23-2021, 06:19 PM
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rv6ejguy rv6ejguy is offline
 
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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.
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Ross Farnham, Calgary, Alberta
Turbo Subaru EJ22, SDS EFI, Marcotte M-300, IVO, Shorai- RV6A C-GVZX flying from CYBW since 2003- 445.9 hrs. on the Hobbs,
RV10 95% built- Sold 2016
http://www.sdsefi.com/aircraft.html
https://www.youtube.com/channel/UCiy...g2GvQfelECCGoQ


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  #30  
Old 02-24-2021, 09:24 AM
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DanH DanH is offline
 
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Quote:
Originally Posted by rcpaisley View Post
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.

Quote:
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.
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