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  #1  
Old 09-18-2019, 03:57 PM
flashverde flashverde is offline
 
Join Date: Jun 2019
Location: tacoma
Posts: 17
Default Efii conversions in the Pacific NW????

If anyone in the Tacoma/Seattle area has done an Efii conversion to their engine, I would really appreciate you sending me a pm so I can contact you. Am considering this conversion and want to see other ones and talk to the owners.
Thanks
Mike
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  #2  
Old 09-18-2019, 05:13 PM
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Toobuilder Toobuilder is offline
 
Join Date: Jul 2009
Location: Mojave
Posts: 4,530
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Are you looking for experience with the efii "brand", or electronic fuel injection in general?
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WARNING! Incorrect design and/or fabrication of aircraft and/or components may result in injury or death. Information presented in this post is based on my own experience - Reader has sole responsibility for determining accuracy or suitability for use.

Michael Robinson
______________
Harmon Rocket II -SDS EFI
RV-8 - SDS CPI
1940 Taylorcraft BL-65
1984 L39C
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  #3  
Old 09-18-2019, 06:43 PM
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rvisnext rvisnext is offline
 
Join Date: Oct 2014
Location: WA
Posts: 70
Default EFII

I have the EFII system 32, PM sent
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  #4  
Old 09-19-2019, 10:31 AM
flashverde flashverde is offline
 
Join Date: Jun 2019
Location: tacoma
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My interest is in efii in general, not just the brand EFII
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  #5  
Old 12-06-2019, 12:39 AM
Thor RV10 Thor RV10 is offline
 
Join Date: Feb 2016
Location: Stanwood, Wa
Posts: 36
Default EFII RV10 KAWO

I am using EFII in my rv10 for 800 hrs now. I am using system 32 for about 20 now. You are welcome to contact me, I am in Arlington KAWO.
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  #6  
Old 12-11-2019, 11:20 AM
keitht keitht is offline
 
Join Date: Jun 2016
Location: coupeville wa
Posts: 103
Default EFI Considerations

During the time when I was considering the configuration of the engine I was going to build and install in the RV-7A I am building I gave serious consideration to using a EFI system. The factors that seemed relevant to work into the trade study were: performance, cost, availability, reliability, failure modes, maintainability, weight, other system considerations and long term availability of components. All of the suppliers in the market for installing on a Lycoming or Lycoming clone are single string systems that are modifications of automobile EFI systems. (At least all the ones I looked at were). So with a single power source and at least some level of single point failures there is the real probability that a single failure could result in an engine stoppage and if that probability is not as unlikely as the numbers for the combined probability of loosing both ignition systems (magneto or P mag) then there is a clear trade off of performance (compared to a hydromechanical system) against availability. Trying to quantify that trade is where the difficulty comes in. If the performance advantages are high and the availability hit is small it may be a worthwhile trade and it depends on the mission you set for the airplane. If you are looking for a reliable cross country airplane compared to a Reno racer you may be more or less inclined to accept the trade and consequences of an engine stoppage. The numbers for a duel independent similar ignition system are probably somewhere in the region of one failure in 10E-8 per hour for failures that result in total loss of ignition and engine stoppage. For a single string EFI it is hard to imagine the numbers being much better than one failure in 10E-5 per hour (if they are that good). The big difficulty with the system architecture of any dual channel EFI is the point of combining and how to make the switch over from one channel to the other. The overall system failure rate is defined by the failure rate and failure modes of the switch and the switch control mechanism and that requires some really careful and clever engineering that I couldn't find in the commercial offerings. It really is hard to make electronic EFI systems more reliable and desirable than a hydromechanical system unless you are prepared to trade everything including availability against performance. If you are a Reno racer that may be OK.

KT
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  #7  
Old 12-11-2019, 12:49 PM
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rv6ejguy rv6ejguy is offline
 
Join Date: Mar 2005
Location: Calgary, Canada
Posts: 5,610
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We've offered dual redundant ECUs since 2015 and this is the choice of the majority of aviation buyers now.

Each ECU board has separate power and ground wires and separate sensor suites. Each ECU runs one set of spark plugs at all times. We only use one set of injectors and can switch control of those over to either ECU via a pilot controlled switch and relays which also isolate from the other ECU. We also have dual electric pumps.

Reliability of our systems is well proven over 24 years, 2000 ECUs and 700,000 flight hours in aircraft. The base architecture has it's roots in our automotive fuel and ignition controllers (total over 10,000 delivered with something over 20 million hours on them collectively).

You do need a robust electrical system having either two batteries or two alternators which can be fully isolated from each other as you're electrically dependent.
__________________

Ross Farnham, Calgary, Alberta
Turbo Subaru EJ22, SDS EFI, Marcotte M-300, IVO, Shorai- RV6A C-GVZX flying from CYBW since 2003- 439.3 hrs. on the Hobbs,
RV10 95% built- Sold 2016
http://www.sdsefi.com/aircraft.html
http://sdsefi.com/cpi2.htm



Last edited by rv6ejguy : 12-11-2019 at 12:53 PM.
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  #8  
Old 12-11-2019, 01:49 PM
keitht keitht is offline
 
Join Date: Jun 2016
Location: coupeville wa
Posts: 103
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Ross,

I think we have had this discussion before and each to his/her own way of thinking about this issue. I have no issues with having two similar channels with a pilot controlled changeover switch. I have seen ignition systems that have a single set of plugs for a corvair engine used in a LSA that had two coils and a changeover switch - a partial solution to the issues of dealing with mismatched component unreliability. The big issue in my mind is does the trade in cost, availability, system collective failure rate, system requirements for two full capability electrical systems and the resulting maintenance and possible issues of flying back to base on a single system in the event of a failure offset the extra performance and lowered fuel burn potential of an EFI system over a conventional hydromechanical system which probably has demonstrated reliability and availability far exceeding all of the single engine EFI installations currently flying. Its a valid question. I have dual P Mag ignition systems on the IO360 in my RV-7A. I made the decision after looking at the trade study conclusions and the available data and felt it was justified. The Pmags having PMG's that provide power above 800 RPM was a significant positive factor. A similar configuration consideration regarding selection of a composite constant speed propeller versus a Hartzell aluminum constant speed propeller put the aluminum propeller way out front (for me) due to the maintenance requirements for any of the composite offerings. Others may chose to weigh the trades differently.
Having a few thousand hours in sailplanes and having landed in a lot of fields on crosscountry flights I have no desire to put an RV down in a field - it usually doesnt turn out well no matter how good you are or how lucky you get.

As Alan Mullaly used to say when he was head of Commercial Airplanes at Boeing "the data sets you free- lets see the data - keep the opinions to yourselves"

KT
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  #9  
Old 12-11-2019, 07:06 PM
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rv6ejguy rv6ejguy is offline
 
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Quote:
Originally Posted by keitht View Post
Ross,

I think we have had this discussion before and each to his/her own way of thinking about this issue. I have no issues with having two similar channels with a pilot controlled changeover switch.

The big issue in my mind is does the trade in cost, availability, system collective failure rate, system requirements for two full capability electrical systems and the resulting maintenance and possible issues of flying back to base on a single system in the event of a failure offset the extra performance and lowered fuel burn potential of an EFI system over a conventional hydromechanical system which probably has demonstrated reliability and availability far exceeding all of the single engine EFI installations currently flying. Its a valid question. I have dual P Mag ignition systems on the IO360 in my RV-7A. I made the decision after looking at the trade study conclusions and the available data and felt it was justified. The Pmags having PMG's that provide power above 800 RPM was a significant positive factor.


As Alan Mullaly used to say when he was head of Commercial Airplanes at Boeing "the data sets you free- lets see the data - keep the opinions to yourselves"

KT
We have something over 1400 single ECU systems flying including the one in our company RV for 17 years. My guess is these single ECU systems account for about 500,000 of the 700,000 total flight hours on our ECUs. I've listed our failure data previously on VAF but it's pretty much impossible to compare mechanical system MTBF rates vs. EFI/EI since I don't have reliable data on the former. If you have some data, please present it here, otherwise, you just have an opinion which isn't worth much as you state from your quote above.

Just what facts do you base your assumption that "probably" hydromechanical systems are much more reliable than a single EFI system?

I am interested to know what "trade studies" you looked at to conclude that P mags would be a reliable choice for you? Most people here know the teething troubles they went through. Would you say that a the multiple spinning parts like gears, shafts, bearings, and electronics operating in a hot environment improve reliability over a system with cool electronics and no moving parts outside magnets on the crank hub? Do you feel 100 hour inspections are a step forward over magnetos? If so why?

I'll ask another question here- do you have any experience flying EFI systems?

I don't do much maintenance on my dual battery setup. Batteries get load tested once per year and changed out about every 5-6. My 2 batteries weigh 4.4 pounds, so no big weight penalty

I absolutely agree with your first sentence. If you don't want to fly EFI, that's your choice and everyone else's too. It's even ok if this is just based on feelings. I've always said you should feel comfortable with engine, prop, systems and avionics choices on your aircraft. I fly a Subaru engine but I certainly don't think that everyone should follow my example...
__________________

Ross Farnham, Calgary, Alberta
Turbo Subaru EJ22, SDS EFI, Marcotte M-300, IVO, Shorai- RV6A C-GVZX flying from CYBW since 2003- 439.3 hrs. on the Hobbs,
RV10 95% built- Sold 2016
http://www.sdsefi.com/aircraft.html
http://sdsefi.com/cpi2.htm



Last edited by rv6ejguy : 12-11-2019 at 08:04 PM.
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  #10  
Old 12-11-2019, 10:03 PM
keitht keitht is offline
 
Join Date: Jun 2016
Location: coupeville wa
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Quote:
Originally Posted by rv6ejguy View Post
We have something over 1400 single ECU systems flying including the one in our company RV for 17 years. My guess is these single ECU systems account for about 500,000 of the 700,000 total flight hours on our ECUs. I've listed our failure data previously on VAF but it's pretty much impossible to compare mechanical system MTBF rates vs. EFI/EI since I don't have reliable data on the former. If you have some data, please present it here, otherwise, you just have an opinion which isn't worth much as you state from your quote above.

Just what facts do you base your assumption that "probably" hydromechanical systems are much more reliable than a single EFI system?

I am interested to know what "trade studies" you looked at to conclude that P mags would be a reliable choice for you? Most people here know the teething troubles they went through. Would you say that a the multiple spinning parts like gears, shafts, bearings, and electronics operating in a hot environment improve reliability over a system with cool electronics and no moving parts outside magnets on the crank hub? Do you feel 100 hour inspections are a step forward over magnetos? If so why?

I'll ask another question here- do you have any experience flying EFI systems?

I don't do much maintenance on my dual battery setup. Batteries get load tested once per year and changed out about every 5-6. My 2 batteries weigh 4.4 pounds, so no big weight penalty

I absolutely agree with your first sentence. If you don't want to fly EFI, that's your choice and everyone else's too. It's even ok if this is just based on feelings. I've always said you should feel comfortable with engine, prop, systems and avionics choices on your aircraft. I fly a Subaru engine but I certainly don't think that everyone should follow my example...
Ross,
It wasn't my intent to get into a fight about EFI or any other technology that we have the choice to put on an experimentally certified airplane or not.
When comparing hydromechanical with EFI it should be pretty obvious when looking at the number of parts in a hydromechanical system, their failure rates and failure modes and comparing that with the number of electronic components, mechanical components, solder joints, software and dependence on dual independent electrical power that there is a need for a alternate channel with a reliable switch over for the EFI. There is a lack of published data comparing predicted failure rates with actual demonstrated failure rates for either hydromechanical or EFI. If you have data comparing predicted failure rates with actual failure rates and the same for failure modes and effects and are prepared to share that data that would be an industry first in the experimental world. The experimental hydromechanical FI systems are very similar to the certified hydromechanical FI so it would seem reasonable to expect similar failure modes and availability with no need for a second alternate channel.
As with the discussion on alternators if the volume of product is sufficient then the very high cost of doing the design engineering, analysis, development, testing and continuous improvement and support to meet predicted performance is justified and necessary to compete and stay in business. If DO178 software and DO254 hardware standards are not being used then the question is "what standards are being used and how do they match up".
Pmag have a following just as your remote mounted EI system does. I am not going to discuss the process I used to determine that using dual Pmags would work for me other than to say it satisfied my concerns about having a total loss of engine power and bounded the risk with numbers I could live with.
As far as experience with EFI for piston engine aircraft the answer is no I don't. My experience is with gas turbine engines for turboprop and helicopters and fly by wire systems for commercial and military aircraft. When I see an EFI for piston engines that is certified, affordable and cloned in the experimental world then maybe I will take another look at doing a retrofit to reap the benefits.

KT
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