# Another engine theory Q - Blowers?

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#### TFF

##### Well-Known Member
For a manufacturer and insider, of course you are not goin back to carbs. You with none of your knowledge, how would you answer the question? If you are honest, you are 50/50 on which way to go.

It’s good that you have so many in the field; that means more data for programming. That does make it more plug and play. These questions are always attached to price, though. I can only afford one way or the other really means they can afford either and they are taking a stab at what they hope they can survive with. If I was building an RV 10 EFI would be on the table. A single seat or budget two seat plane, EFI would not be even dreamed about. It’s not if something exists, I want it; things are at levels. Sometimes it’s the wrong solution. For a Sonerai, I don’t want to support the level of electrical needed. It’s not about it being a bad product for any brand, it’s realistic expectations. If it’s your game, you would be a fool to not. But it’s an example of like a gold watch, if you have to ask, you can’t afford it. Afford doesn’t have to mean money either.

#### rv6ejguy

##### Well-Known Member
For a manufacturer and insider, of course you are not goin back to carbs. You with none of your knowledge, how would you answer the question? If you are honest, you are 50/50 on which way to go.

It’s good that you have so many in the field; that means more data for programming. That does make it more plug and play. These questions are always attached to price, though. I can only afford one way or the other really means they can afford either and they are taking a stab at what they hope they can survive with. If I was building an RV 10 EFI would be on the table. A single seat or budget two seat plane, EFI would not be even dreamed about. It’s not if something exists, I want it; things are at levels. Sometimes it’s the wrong solution. For a Sonerai, I don’t want to support the level of electrical needed. It’s not about it being a bad product for any brand, it’s realistic expectations. If it’s your game, you would be a fool to not. But it’s an example of like a gold watch, if you have to ask, you can’t afford it. Afford doesn’t have to mean money either.

I didn't say I wasn't going back to carbs (though I'm not), I said the vast majority of our 2000+ aviation customers are not.

We don't sell too many full EFI setups for VWs due to the EFI price vs. the engine price. Are selling more and more EIs to VW guys though who are sick of mags and other crappy EIs out there.

Lots of 4 cylinder Lycos going to SDS too. At this level, the EFI is cheap compared to $30K+ worth of glass panel most folks don't need, but want for VFR airplanes these days.$6-$8K for dual ECU EFI and EI doesn't make too many flinch when we're talking$100-$250K airplanes. The setup is about$1K more roughly than 2 new mags and a RSA-X, AFP or Silverhawk FI setup.

Certainly EFI isn't for everyone or every mission and I've talked several potential customers out of it as I don't think it's the best choice for some of them.

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#### PMD

##### Well-Known Member
I didn't say I wasn't going back to carbs (though I'm not), I said the vast majority of our 2000+ aviation customers are not
Don't want to put you on the spot (OK, I guess really DO!!) but what do you rate the chances of an STC electronic injection retrofit coming to market...and when? I would LOVE to have a 390 Lyc with EI and EFI in an AA5B airframe. Yeah, I would much rather have a very light weight turbo diesel and head for the teens, but for the time being I can buy a Tiger, I can convert an A4K or I could stuff in a 390 and REALLY make that thing boogey. Between the two electronics and the extra 30 cubes, I estimate I could have 30 or more extra HP on the same or even less fuel.

#### rv6ejguy

##### Well-Known Member
Don't want to put you on the spot (OK, I guess really DO!!) but what do you rate the chances of an STC electronic injection retrofit coming to market...and when? I would LOVE to have a 390 Lyc with EI and EFI in an AA5B airframe. Yeah, I would much rather have a very light weight turbo diesel and head for the teens, but for the time being I can buy a Tiger, I can convert an A4K or I could stuff in a 390 and REALLY make that thing boogey. Between the two electronics and the extra 30 cubes, I estimate I could have 30 or more extra HP on the same or even less fuel.

I would say not very likely due to the costs and time involved to satisfy the FAA requirements for such things. The low production rate would put the price out of sight on a per unit basis. I believe the Aerosance and Lycoming FADECs were $10-$20,000, years ago, depending on model. Aerosance came out around 20 years ago but never caught on much.

You could maybe convert a Tiger to OM and then do this. I have a couple customers with OM airplanes using our EFI and EI.

#### PMD

##### Well-Known Member
You could maybe convert a Tiger to OM and then do this. I have a couple customers with OM airplanes using our EFI and EI.
Sadly, I can't go OM since most of my business is South of 49. Two things would solve that problem: The US would recognize OM and allow airplanes in or the order to re-write FAA part 23 stuff ever got done to bring the genav business back to the US but out of the hands of lawyers and insurers (i.e. terminate the LLL = Legal Liability Lottery).

I have only been involved in one STC (my design but completed and STC'd by my friend - great engineer - and BTW known as Craftsven on these pages) and having been done in Canada it was fairly straight forward. But, that was 40 years ago, so can't say that is still the case.

It REALLY bothers me that we have let government get so out of control that they have doomed the future of general aviation in North America remaining rooted deep in our now very obsolete past. I will now kick my soap box aside and resume morning coffee. Meanwhile, my lust for angle valve heads will go unrequitted.

#### TFF

##### Well-Known Member
OM has a hard road in the US because of all the homebuilts and airports and A&Ps. FAA will say there are other lanes. Always have Experimental Exhibition too. FAA will not allow it to go both ways. OM has a foothold in the expansiveness of Canada and small population and other considerations. You can always do what some do which is, don’t get caught.

#### Aviacs

##### Well-Known Member
VWs are a known quantity on Sonerai s, even bolted to ones that aren’t fully. You will not be cheaper with a VW prop drive with EFI over a conventional engine. Definitely not more reliable even if reliability isn’t a concern. If it’s your dream combo, probably worth it; that means you are interested in wrenching as much as flying. The guy with the A-65 powered Sonerai that use to be on the forum though it was a great combo. I think his issue was it wasn’t a buy and fly as he first thought and that the engine although a runner was pretty worn. My friend had two RV3s both had 320s. I would be picking a 235 as the in between. I’m actually not held up on an airplane engine as the only way, but the ones who do use them just do and will forge through the problems and solve them themselves. They might ping ideas, but it’s going to be their solution. Thinking any combo of EFI or prop drive is off the shelf is going to make for a miserable experience. We will give the VW a 50% pass on off the shelf. It’s a wrencher’s game.

TFF - You've responded to nearly every post i've ever made on HBA with thought, wisdom and apparently a lot of experience.
I appreciate the effort you make.
The mistake you make is in thinking that posts like mine are asking for wisdom.
They are not.
They are asking for neutral facts. Or a whole array of them.
As someone else noted, i'm near fully grown up, at least the groan part these days, & can apply whatever "wisdom" or not has accrued to me by this point. Often, as you allude, the wisdom will be driven by economics.

To the point of this post, from an economic standpoint and from watching how VW aircraft engines fail over the years, EFI as currently developed seems like a cheap first step building block whether a person takes if further or not. Sensible/cheap might = build conventional carburetor engine, no further development. Next step before any other building block today seems to = change induction & Ignition to EFI.

It would certainly be economical to go all non-electric. But i like to travel in an airplane when possible (& within my personal construct of "travel"). That = speed (Insofar as possible) reliability, and an electric system. Although it is armstrong start, this airplane is equipped for Canadian night flight, has electric transfer pump for fuel from the wing tanks, & has an MC transponder. I'll probably add or convert to ADS-B. In your opinion, no doubt i 'm working with the wrong platform. Maybe i'll expire or become incapacitated before flying it - that happens routinely. For instance, my RV-3 kit came via the retirement machine shop of a former LI manufacturer who passed before his dream was complete. Sold in a sad pile of wings, empennage, and parts in the corner of a storage barn where heirs had relocated it; and listed in the auction as "scrap aluminum - possible airplane parts"....None of us really know what the final disposition will be.

My goal is to attain information, dial in my personal iterations, and have fun along the way as far as i can afford it.
To answer one comment (possibly not yours) all my life i've spend building stuff. It does seem to be where i gravitate.
I'll most likely die when i can't build anymore, <whether that is a health factor, or an economic issue> . Not when i can't fly.

PS Re: A65 in Sonerai - a lot of people have done it, it tends to be an awkward fit, though i might consider it if someone sent me an A65 -9 that could be adapted for electric?. My friend Bob Aymar (Aymar Demuth props) pancaked one off the end of the runway into a flood control berm at FDK some 45 years ago. He was averse to VW power but the Continental let him down.

smt

PS: what is OM?

#### Hot Wings

##### Grumpy Cynic
PS: what is OM?

Owner Maintenance

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Over the years I've seen some pretty scary suspension/brakes/steering under some of the owner maintenance cars that came through my shop. A few were there because they did in fact cause an off road adventure. Yet we allow this on our roads without a second thought. The system seems to work well enough on our roads with what I perceive to be a much higher risk to the general public so why not allow it for our personal non-commercial aircraft as well?

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#### PMD

##### Well-Known Member
Owner Maintenance
edit:
Over the years I've seen some pretty scary suspension/brakes/steering under some of the owner maintenance cars that came through my shop. A few were there because they did in fact cause an off road adventure. Yet we allow this on our roads without a second thought. The system seems to work well enough on our roads with what I perceive to be a much higher risk to the general public so why not allow it for our personal non-commercial aircraft as well?
I wish I had been a fly on the wall at the MoT meetings that put the Owner Maintenance regs together. My feeling is that we grant the E/AB crowd full license to design, build, maintain and fly something of their own concoction, so why not let the same sort of person who wants to use a certified airframe to modify or not and maintain and operate as they would an E/AB? In my few years as an aircraft maintenance shop owner (NOT, unfortunately an AME - would have done that but got into the car business by accident instead) I have seen some pretty scary airframe, landing gear, engine work come into our place. We stopped doing private aircraft because we NEVER found a single one that was actually legal from an airworthiness standpoint, and rapidly gained a reputation as the "expensive" guys - so commercial only from then on. So, I am not all that upset about the idea of John Q. doing his own airplane thing - as I expect most who decide to do so are at least a little informed and aware that their continued ability to breathe depends upon some level of sense being applied. I am just plain shocked (and DELIGHTED) that our bureaucrats could pull this off. Had it not been for the boing-boing Max incidents, there might have been a chance to do so in the Hewessay, but the army of marauding ambulance chasers who's gluttony has been spiked by Max will prevent that, I fear.

oh, on edit: the accident records have shown that the OM programme has not seemed to show any real differnce statistically in safety.

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#### TFF

##### Well-Known Member
We are lucky enough it’s not the opposite where autos have to have certified mechanics. I think the why is the auto world got by before the government figured out it could tax and control it.

#### rv6ejguy

##### Well-Known Member
A piece of paper doesn't mean much. I've seen scary work done by certified auto mechanics as well as AMEs, (A&Ps to our American friends). You either care and know how to do the job properly or you don't. The cert doesn't mean you do great work.

#### PMD

##### Well-Known Member
We are lucky enough it’s not the opposite where autos have to have certified mechanics. I think the why is the auto world got by before the government figured out it could tax and control it.
This would be an OEM's wet dream come true. As it is, up here we don't have anything like Moss-Magnusson act and manufacturers can deny warranty if they decide they don't like who or what did something to "their" car. As it is, it is sometimes difficult to impossible to get some manufacturer's actual diagnostic software (OBD II has about 3,000 codes, but they are generic. OEM specific codes can number into the tens of thousands and give you access to many variable settings within the control unit(s). They would LOVE to force you to come to them and them only for the rest of the life of the vehicle - and cars are becoming so software dependent they are almost at that point. Of course, to them "certified" means certified by OEM, not government or trades association.

#### PMD

##### Well-Known Member
The EPA and auto makers are pushing hard to make it illegal to hot Rod a new car, even for off road use, and they are winning, it seems. Just another step to close off owner maintenance. Recognizing the Protection of Motorsports Act of 2021 (RPM Act)
I have been racing karts since we lost our Solo II venue, so had paid no attention to the US car world. **** near fell over and cried reading that!

#### BRAAP

##### Member
. As it is, it is sometimes difficult to impossible to get some manufacturer's actual diagnostic software (OBD II has about 3,000 codes, but they are generic. OEM specific codes can number into the tens of thousands and give you access to many variable settings within the control unit(s). ....

Interesting you mention this now. Short version is in all my years playing and tuning factory automotive EFI systems, in particular the early Japanese version of the L-Jet, and dabbling with some aftermarket, MegaSquirt, Wolf EMS, I have come to appreciate what the OEM auto manufactures bring to the table with some of the tuning software available. In particular I have become quite fond of the GM Gen-III 411 PCM utilizing HP-Tuners over the past 10+ yrs dabbling with it. For an aircraft application my draw to it is mostly for the already proven long term reliability over extreme temperature and environmental exposures, (that is a HUGE one for me in regards to aircraft EMS), the ability to control not only fueling but ignition across all the environments an aircraft power plant will experience and with good precision. Down sides are obviously in implementing a second redundant system on the same power plant, implementing the crank and cam triggers, the time spent nailing down the specific fueling and ignition advance values for a particular power plant, and the weight of the GM PCM is much heavier than most aftermarket computers, double that in a redundant configuration.
Other plusses include ability to utilize select portions of the OBD-II system for a closer watch over the power plant for potential failures such as misfires of specific cylinders, fueling issues if O2’s retained, engine knock to somewhat of a degree if Knock sensors utilized, (this topic due to its specifics and its staunch supporters both for and against is worthy of its own dedicated discussion thread, let’s not get into that debate here), ability to alter target fueling to be Stoich or slightly above or below or tune exact desired AFM’s for a given load setting utilizing wide band... etc. It’s versatility as a stand alone EMS is impressive, at the expensive of what it takes to implement.

Another alternative as mentioned already, SDS is worth considering. Over the many years of tinkering and wasting time dabbling w/older automotive OE systems I have kept an eye on SDS, mostly in the mid to late 90’s. Many Emails back and forth with Ross back then, sadly I never pulled the trigger to use that system, always had a lame ass excuse... well they are still around because it works! Robust, reliable, cater to Aviation, have refined over the years, proven reliability, the “easy button”. (I am not in way paid to promote or endorse, just my personal opinion).

If not already, would like to see a discussion about utilizing GM 411 PCM in aviation applications

#### dwalker

##### Well-Known Member
Mmmm....I dislike OEM systems for the most part, but GM is kinder than most. My least favorite was the "multi layer adaptive" architecture used by Ford, Subaru and some others that will gradually negate any change, and VWs nightmare ecus that go into limp mode if the back door sensors are missing, or the torque sensor reading didn't match what the 02, TPS, and boost readings are.

No Sir, give me a solidly proven aftermarket ecu that I can use any sensor, trigger pattern, staged injection, auto tube or target lambda or whatever.
I like AEM because of a couple decades using it. I dislike Motec because I hate paying three times for something. I've only had contact with a single SDS product, an ecu in a Mazda Protégé with a turbo engine in it. It worked fine.
At this point I have used Wolf 3D, Weber Marelli, Bosch Motorsports, Haltech, Electramotive Tec2 and 3, Vems, Viper, ProEfi, DTA, Gems, AEM, Zytec, Autronic, Adaptronic, 034, Holley, and a bunch of other weirdness. Some works and some... doesn't. I just know what I would use when I want an engine to start and run every time the key is turned or the button pushed.

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#### PMD

##### Well-Known Member
I have some friends who make stand-alone EMS boxes and we have discussed their potential use in aircraft applications. Typical of most electronics freaks is that they believe their stuff is so simple and reliable, they can't imagine why I keep insisting that an aircraft needs two completely redundant systems, including ever signal source. I am not inflicted with digitalis, so IMHO every un-neccessary line of code or feature is just one more thing to go wrong or carry. That said: I fully understand and agree that OBD2 diagnositics make absolute sense so that anyone can read codes with OTC hardware.

#### dwalker

##### Well-Known Member
I have some friends who make stand-alone EMS boxes and we have discussed their potential use in aircraft applications. Typical of most electronics freaks is that they believe their stuff is so simple and reliable, they can't imagine why I keep insisting that an aircraft needs two completely redundant systems, including ever signal source. I am not inflicted with digitalis, so IMHO every un-neccessary line of code or feature is just one more thing to go wrong or carry. That said: I fully understand and agree that OBD2 diagnositics make absolute sense so that anyone can read codes with OTC hardware.

When I started down the EFI path for my flight engines I Immediately wanted redundancy on everything. Then I did not. First and foremost is that the complexity and added weight in sensors, brackets, wiring, ECU, batteries, etc. got really interesting really fast. Then I started paring down. If the intake air temp sensor fails, then we set it to fail to a "safe" temp so the engine will not run as efficiently but it will run, and I get a flashing warning on the display telling me something is not right. Same for CHT, etc. The only three I cannot get away with that is the cam/crank sensors and the MAP sensor. The map sensor can default to a setting where the engine just runs very rich but again, will still run. The engine positioning sensors I can have backups of, but then again, I have not had a cam/crank sensor fail in maybe a decade where there was no physical damage to the sensor present.
Well, what about ignition coils and injectors? Those fail right? MMM sure. But likely not in the lifetime of an aircraft. The thing is using a coil and injector per cylinder lessens cycles and it is very very unlikely to have a failure of more than one at a time. Even a clogged injector will still deliver enough fuel for the engine to run, again, not as efficiently and again, it is something that if you have your system set up right you will know about before it gets to the "serious issue" point. Again, this is as simple as setting up an alarm in the ECU to flash a warning on the display along the lines of "INJ 3 EXCEEDING TRIM" or whatever. Ignition coils, at least the Denso coils I tend to use, never fail without warning. In every single case the coil has first degraded performance with a slight misfire the ECU detects and again, warns you of. Again, not a failure mode where the engine stops or loses power to the point you might as well shut the engine off, but a loss of smoothness and power at peak rpm and load. Still, if in doubt replace once every 100 hours., easy and relatively cheap.
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In the end, I understand many are not comfortable with EFI, and that is OK.

#### rv6ejguy

##### Well-Known Member
Most folks use what they have experience with and are comfortable with. I've worked with a bunch years past and found many overly complicated for running an aircraft engine which spends most of its time at relatively constant power settings and low rpm. Seen SW and noise issues on some high end brands, no brand is immune to these things.

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