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SDS EFI in 2020

Supply Update

At this point in time, we are starting to see some difficulties in getting certain sizes of 6061-T6 and 7075-T6 billet. We've managed to source some from alternate suppliers for most runs so far although delays of this aspect have pushed back production schedules on some parts.

The anodizing shop is operating with reduced staff which has tripled delivery times unfortunately.

We are effectively sold out of CPI-2 PCBs and dual enclosures at this time. Probably at least 4 weeks to have new stock on the shelf given the current lead times.

Our order of CT clamps from Germany placed 2 months ago has finally shipped so we should be able to start filling some back orders of Lycoming intake flanges next week. Only gold and clear in stock now but more coming off the mills early next week for anodizing. Expect red to be available again around the first week in May.

We are currently running more PV Lycoming valve covers. Should be done by Friday.

Generally good stock on EM-5 and CPI components.

If you order something, we'll let you know if all parts are in stock or not. Our policy is to not charge credit cards until all parts are in hand to fill your order.

As always, thank you for choosing SDS. :)
 
I identified an issue with my dual SDS modules this past week and had a visit with Ross to discuss what might be causing it. A couple seconds of me describing the symptoms and Ross came up with the most likely cause and some tuning suggestions to remedy it... The next morning Barry came down to my hangar and within 2 minutes we had the engine humming on either module.
My fuel map settings for the backup FI module were drastically different from the primary module settings & couldn't figure out why. As it turns out my Engine Temp values were skewering the fuel map, resetting with the proper values & all good!
This weekend I did some ground runs to confirm the fix, than took off on a short 3 airport hop to check the setting changes. All works great now, Thanks again Ross & Barry!

I'm so pampered to be a few buildings down the road from Racetech & the boys...
 
Glad that's all remedied now Ralph. Hopefully we can get flying again and shoot some video when this virus deal is done.

On the supply chain front, we've experienced a few slowdowns on some components sourced out of the US lately. These were finally shipped today so hopefully we'll be in good shape again by next week.

We are seeing longer shipping delivery times both to us and from us. This slows down the upgrade processes as well as production somewhat.

We've had a huge demand on billet valve covers, intake kits and flywheels as of late. Just got a big batch of PV covers in last week, more flywheels in process now and more flanges will be out of anodizing soon.

Thanks for all the orders guys but sorry some are taking so long to fill. We're doing our best with 3 CNC machines running our parts today at one shop. Trevor is chewing through billet at a ferocious rate. Doing our small part to keep billet suppliers in the US and Canada busy!
 
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Slight Price Increase, update

We've had a slight price increase on our 4 cylinder kits of $60 to help offset increased costs of materials and extra hardware supplied.

Prices had been held the same for about the last 2 years but with a sharp increase in colored Tefzel wire costs recently and the addition of extra CNC'd bits supplied as standard, we've had to make up some of this loss.

We also have the option of twin wing root fuel filters to replace a single, central mounted pump pre-filter if desired.

For the most part, our parts suppliers have been able to supply in close to normal timelines. We've done a large buy of several components which may have a shortage in the near future due to production stoppages at the manufacturing level recently. This should carry us through 2-3 years hopefully.

Thank you to the many folks who've ordered Lycoming CNC billet parts this month. Wow. My machinists, anodizer and billet suppliers are happy. This helps in a small way to keep Americans and Canadians working through the current economic slowdown. We are happy to be buying over 70% of total parts and components from US sources. You support us, so we feel we should return that favor. We hope to see more industry and production return to the US from overseas in the coming years with the recent impetus in that direction.
 
Fuel Pump Modules

We had a big rush on fuel pump modules this month and are sold out right now. More are at the anodizer now so should have early this week.

Ditto on the fuel pumps to go in them, ordered a couple weeks ago and should be here this week. Shipping of these and billet material has been a bit slower this month, hence the longer delays.

Thanks for everyone's patience here.
 
Lots of fuel pump modules in hand now for those who wanted them.

We've been forced to buy up large quantities of aluminum billet due to the scarcity of some sizes to machine our parts.

Ditto on LCDs where we cleaned out our US supplier last week to ensure we had a good supply to manufacture our various programmers for some time to come. Supply of these is uncertain in the future and we are engaging new suppliers for samples to test and possibly switch to if our traditional sources dry up.

We expect completed CPI-2 PCBs to ship from the loading facility on June 23rd. Unfortunately we can't fill any orders for these until after that date.
 
RV-7 in Spain

Congrats to Rafa Navarro who just made his first flight a couple days ago with SDS EFI. Very clean looking build. :)

 
Dual 6 Cylinder EM-5 Wiring

Les Kearney was kind enough to share his very nicely done wiring schematics for his RV-10 which I've added 2 new links to the top of the Documentation section on our aircraft page: http://www.sdsefi.com/aircraft.html

He shows how he integrated SDS and other systems into his G3X as well.

There is a shortcut link just above the YouTube logo and link, entitle "Docs" or scroll down to near the bottom of the page to the "Aircraft Manuals and Documentation" heading.

I like what Les has done here and it's been flight proven now for some time- which is important in my books.

Les' RV-10 is the one featured in several of our YouTube videos and again I'd like to thank him again for his feedback, ideas and opportunity to fly in his awesome -10.

Les has also been very active in the -10 community, sharing his ideas, experiences and info with other -10 owners. All around friendly, smart and nice guy. :)
 
Exciting Day

My friend Trevor, who does the largest percentage of CNC work for us, recently took over the adjacent bay to expand his operation.

Today he took delivery of a third HAAS mill- a VF-4 SS (super speed). This is much larger, faster, stiffer than his other mills with 12K spindle speed and up to 130 ipm feeds and a 4th axis.

Trevor's shop is all HAAS and he's had excellent service from them starting 18 years ago. If you are not familiar with HAAS, they sell more "real" CNC mills than any other company in the world and are made in the USA with something like 97% US made components and sub-assemblies. HAAS is a success story you Americans can be proud of.

Since we Canadians like you guys so much, we are happy to support great US companies like this. Seriously, you buy our stuff and we want to return that favor by supporting US companies. Truth be told, we couldn't make what we make without US raw materials (lots of aluminum from OR and WA), wire, hardware and components.

Here is hoping the US (and Canada) start bringing back more industries and jobs to the continent. :)

SDS and Trevor are both hoping that this VF-4 will cut parts lead times from weeks (or months:() to days, so I have to apologize less for delays.:eek:
 

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Order Backlog

Thanks to many folks on VAF, August was our biggest month since 2005. Amazing sales growth this summer.:)

With this volume of orders, our backlogs have stretched out to nearly 3 weeks on some items despite again working 60 hour weeks.

Valve covers are back in stock again so we'll try to get those orders filled this week.

More induction flanges are machining this week so we can fill some custom color options next week.

Multiple EM-5 orders are underway for this week again.

We are just finishing the Rotax installation manual and 2 new parts for the kits we decided to add are being machined now. Release of the first of these kits should happen around Sept. 10 with a second batch to follow around 2 weeks later.

Video production is taking a back seat to parts production lately but I hope to have another done soon. Thanks for all the kudos from our YT audience.

And thanks to everyone for their support and patience!
 
Update and a Caution

The new Gen 3 Rotax 912 EFI kits will start shipping to initial customers next week.

A word of caution on EFI installations and I've mentioned this before here, never tie wrap engine sensor cables to spark plug wires. This is poor practice and often leads to engine running issues which can be difficult to diagnose. Just spent several weeks here trying to figure out a running issue on a plane in NC which turned out to be caused by this.

Inductive and capacitance coupling can be a big deal when you have 25-35K volts on a wire a couple mm away from your sensor input wires.
 
A word of caution on EFI installations and I've mentioned this before here, never tie wrap engine sensor cables to spark plug wires. This is poor practice and often leads to engine running issues which can be difficult to diagnose.

Inductive and capacitance coupling can be a big deal when you have 25-35K volts on a wire a couple mm away from your sensor input wires.

Just how much separation is needed??

Crossing wires at 90* vs. paralleling them make any difference in the level of interference?
 
YouTube

Thanks to the many folks on VAF who have subscribed to our YT channel- today putting us over the 500 mark. :)

Sorry for the lack of flying content lately. Hopefully we can get back to that soon.
 
Parallel for a couple feet is bad, crossing at 90 deg, 1/2 inch away is probably no issue.

Had a buddies subaru 2.5 turbo motor a few years ago that kept braking up under boost above 4500 rpm. This wasn't in a plane, but an off-road car. After hours of diagnosis and not finding an issue, we took it to a Dyno thinking it was a tuning issue. Took the dyno guy 30 seconds to tell us to move the cam position sensor wire. We had it crossing a plug wire at a 90 degree angle, about an inch or so away. Relocated the wire and it ran great. Electrical coupling sucks. I think the only absolute answer is "as far away as needed to not cause issues".
 
I think the only absolute answer is "as far away as needed to not cause issues".

I agree. Further away is better. It's difficult to say how things will be affected.

In the early days starting with the EM-3, we used to test for EMI/RFI issues by placing the the ECU upside down, with the lid off (PCB exposed) on top of the ignition wires to see if it screwed up. With later hard and digital filtering on the EM-4, we could get smooth running until the plug wires were less than 1/2" from the CPU chip (using proper suppression wires).

Another big issue is using non-resistor spark plugs with ECUs. In our testing, these create up to 5 times the interference compared to resistor plugs and I've seen and heard of a number of OEM ECUs equally affected. You should never use non-resistor plugs with digital engine controls.

We've measured over 100 volts induced on wires run close and parallel to plug wires (unloaded). When the logic level differential is only a couple of volts, you can see where this can be a big deal. Garbage in= garbage out. https://www.allaboutcircuits.com/textbook/digital/chpt-3/logic-signal-voltage-levels/

Noise is one of the biggest challenges of developing electronics for aircraft as we have the engine ignition system and multiple electronic systems in close proximity to the ECU and sensor wiring including VHF transmitters and transponders.

Stack the deck in your favor by using good wiring practices. Nobody needs problems like this on an aircraft.
 
Rotax Parts

Some more awesome work from Trevor.

2nd batch of Rotax 912 EFI parts back from the anodizer now. On the right are some new vacuum fittings we decided to supply with the kits to make connections to the MAP sensor and fuel pressure regulator easier. These will be supplied with new hose and constant tension clamps as well. Attach to the factory vacuum balance cross over fittings on the manifolds.

Full speed ahead. :)
 

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a review

I just posted an ad here and saw the SDS post in the "recent posts". Let me just say that, during my struggles trying to get an Eggenfellner STi engine conversion working, Ross and SDS were a real bright spot in the whole mess. Ross was very easy to work with, and very knowledgeable and helpful. After initially getting the Eggenfellner wiring kluge working, I ended up tearing it all out and replacing it with the SDS system. The SDS was easy to install, and provided perfect, reliable control over everything the engine was doing. Detailed tuning was very easy and effective with the SDS system.

I highly recommend Ross and his SDS system.
 
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Thanks for the kudos Brian. We tried to help out all the Egg customers who were left stranded. Quite a number are still flying with their Sube packages.
 
I've got 6 months and about a hundred hours now on my SDS conversion for my IO360, and I have to agree - it was a pleasure to install and work with. Some RTFM is required, but it all makes sense once you do that. There are obviously a lot of hours involved in a retrofit due to raping out all the original engine ignition and fuel systems but the new installation is pretty straightforward and I LOVE the new programmer format. Initial programming was easy, and flying with it and tweaking the map occasionally is just plain fun. I would highly recommend installing the optional AFR/O2 sensor with this system.

I'm regularly seeing 25 nautical miles per gallon now at 165 knots in cruise at mid-teen altitudes.
 
Thanks Greg. You had a couple atypical issues early on so I'm glad you are happy with the system and enjoying it now. Always nice to work with mechanical savvy guys like you. :)
 
SDS EM-5 Startup Problem

Greg, I moved this discussion over here instead of the CPI-2 thread to avoid confusion between the two systems. I hope that's ok.

To recap, Greg is sometimes getting fuel ignition on power up before cranking the engine, which is creating a bang and or prop movement.

________________________________________________________

"If we were a little closer, I'd fly to you and show you myself.

If I power up the fuel pump, then the ECU with fuel pressure available, and then power up the coils, I'll get the pop about one try in five. As mentioned earlier sometimes it's clearly a "wheeeooshhh" as a slow mixture burns through the pipes and sometimes a .44 magnum going off, depending on the mix and distribution, with significant prop movement usually on the louder ones.

I figured out the cause pretty quick, and just let the mags do their thing before I introduce fuel in the system. My start procedure works as long as I shutdown by killing injection first, so it's no big deal now, but food for thought and easily reproducible if you'd like to see it. In my plane the injector power comes on with the same switch as ECU power, two switches for the mags, and separate switches for the fuel pumps."
__________________
Greg Niehues - SEL, IFR, Repairman Cert.
Garden City, TX VAF 2020 dues paid
N16GN flying 700 hrs and counting; IO360, SDS, WWRV200, Dynon HDX, 430W
Built an off-plan RV9A with too much fuel and too much HP. Should drop dead any minute now.

_______________________________________________________________

Thanks for this feedback. With EFI, when you shut off the ECU or injector power, there should be no fuel in the cylinders unless the injectors leak. On a good EFI setup, fuel pressure should be present in the block and lines hours, weeks or months after the last pump run. The injectors snap closed as does the pump check valve and the fuel pressure regulator return valve, trapping the fuel pressure in the system.

Interested if your fuel pressure holds with pump off?

As you correctly said before, the ECU does a short injector pulse if the engine temp is below a certain threshold to aid starting. If fuel pressure is present at lower temps, the injectors will open for a few milliseconds at ECU power on, putting some fuel into the cylinders.

Now, trying to figure out why you are getting a spark happening here and that's the puzzle. It shouldn't be happening and it never has for me with something like 20,000 hours behind SDS on many different engines.
In light of this and the lack of other customers reporting this we need to figure out what's different on your installation.

The ECU shouldn't fire any coils until it sees synch and trigger magnet passage. I wonder if something has crept into software to cause this? You are running a newer version than I am. I'll look up your software version and get Barry to run some bench tests when he gets back, scoping the coil outputs on power up to see if we get spark. We typically run coils and injectors on the bench together as we test each ECU so we should hear a stray spark on ECU power up if that was happening.

I'd like understand why this is happening to get to the bottom if this for you. Thanks for letting us know. This isn't right.

If any other EM-5 owners have experienced this issue, please contact us and state your software version which appears in the programmer display on initial power up. It will be V___ with a burn number beside it. Need to figure out if this issue is unique to Greg or something systemic with certain versions of software.
 
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Correct - I have isolated it to the spark occurring as I power up the mag coils. It may not be happening on every power up either - I only know that I get an ignition about 20% of the time when there is fuel already present in the cylinder and I power up the mag coils. It may be sparking every time and I usually don't get ignition, or it may be sparking once in a while, or even sparking on just one or two cylinders - I have no data for that.

Now I shutdown by killing the ECU first - stopping the injectors and leaving the engine with no fuel. Startup has the mags turned on first before any fuel can be introduced, so if there is spark happening I don't care - then fuel and ECU and then crank. And to answer your fuel pressure question, yes the pressure does stay in the system quite nicely when I shut down. I've played with it, and if I shut down the fuel pumps a half second prior to killing the ECU, I can catch the fuel pressure in the mid-teens and watch the system FWF heatsoak and the pressure will rise to the Borla regulator opening and bleed it to the fuel tank, and then as things cool off it falls again. Remember I'm running 91E10 with high vapor pressure - 100LL might not be able to boil to that pressure, I haven't tried it.
 
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Update

We are continuing to work on the EM-6 software, of which a lot of this code as it's developed and tested, will find it's way into the latest EM-5 system before EM-6 release which is still far off in 2021 (we hope!).

It makes more sense to do the software first as the hardware is usually a quicker task to design and test. We are also designing some new hardware as time permits. Some of this has been a result of soon-to-be obsoleted components which is always something we face in this industry and other improvements we want to introduce.

Sales have been tremendous this year so far, which continues to limit the time we can spend on EM-6 development unfortunately, even with extra people building stuff here.

Our 3 machine shop contractors are churning out tons of CNC's parts with over 1200 delivered so far in October alone.

Thank you to all those VAF members who support SDS!:)
 
You Tube Milestone

Our YouTube channel passed 150,000 collective views yesterday. :)

Thanks to all those here who subscribe and watch.

I've been shooting some more flying content recently before winter closes in and will work on editing that over the coming weeks into a couple more vids.

I also branched off from the EFI side for a bit to do some vids on general engine topics, which I've wanted to do for a while.

On the EFI side, we are still wading through orders placed 2-3 weeks ago and doing our best to get them built and shipped out. Always some new/ improved bits in the works which are being introduced as they become available. Thanks to all our customers for their feedback to help us make SDS even better for the future.
 
Do you guys recommend a sniffle valve for installations running the full SDS system? I know mechanical fuel injection systems need it, but since post shut down leakage should be zero with electronic injectors I'm just curious if I need one.
 
No sniffle valve required. When the ECU or injector power is shut off, the injectors snap closed, so zero leakage.
 
Update

November has been another busy month for us. We sold out of EM-5 ECU PCBs last week but more are to be shipped from the loading facility on Dec. 3.

This break has given us several days to get back in earnest onto EM-6 software development and Barry has made some good progress towards that end. He's slowly knocking "to do" items off the list but we're still many months away from production EM-6 ECUs.

CPI and CPI-2 sales have been steady as has our line of CNC'd parts which has been keeping machinists Trevor and Howard busy as usual. We have a few new and improved parts for the EFI kits which is always an ongoing process.

I've managed to arrange new sources for some of the common ignition components we use, as the original ones often have had very long lead times or spotty supply which is maddening when we are super busy like most of this year.

We don't have any plans to develop kits for any more aviation engines at this time as we have enough business to keep us hopping all year it seems with the present portfolio. This includes Lycoming 235 to 580, Conti O-200 and IO-550, Jabiru 2200/3300 and Rotax 912. We also cover VW, Subaru and GM LS aero conversions with some special parts.

Thanks again to all the fine folks who've supported us and given us valuable feedback to improve SDS products.
 
Question on AFR monitor settings

Ross & Ralph -

Great video, thanks for putting it together.

I noticed in the video that you have the Ballenger unit set to the extreme range. I have mine set the same but had considered changing to the normal range for greater sensitivity. What are your thoughts on the pros & cons of these two settings?

What AFR do you target during high-power takeoff & climb?

I run mine in lambda mode rather than AFR, so I'll have to do some math to compare your values to what I'm seeing on my AFP-injected IO-360. I think my readings are not as steady as what you were seeing.

I also noticed that you are running 5 degrees of LOP advance, which is more than I've been running on my CPI-2. I'll have to do some testing to see if I would benefit from more.

Thanks again!
David
 
To make the Ballinger display on the SDS control head, it had to be set to the 'Extreme range (gas)', the SDS O2 sensor input has to be set to 'AEM (new)' format. AFR display values on both units are not exactly same but within a couple tenths of each other, example 15.2 on Ballenger vs 15.3 showing on the SDS. Close enough for me.
Basically my ignition is set at 25btdc and varies with MAP and RPM ranges, it may retard up to 4 deg or advance up to 4 deg dependent on rpm & load.
Additionally, the Lean Of Peak switch on the SDS advances the timing 5 deg. more than the reactive time described above. The Lean Of Peak switch also leans out the basic fuel map by 26% to give me the 15 - 16 AFR for reduced fuel flow and maintaining reasonable temp changes and power loss. The AFR will still vary a bit as the fuel map is also influenced by the Air Temp, Engine Temp & MAP.
In general High load situations would drag the AFR to around 11.6 - 12 with timing at around 24btdc. In lean conditions I would see AFR about 15.5 - 16 and timing about 33btdc. These would be the intended program parameters I want in the SDS & I still have the lean mixture knob (which I rarely touch anymore) if I want to play with it.

Part of our Ballinger experiment, I power it through a delay relay to see how it affects the life span of the NTK sensor. Power is delayed 30 seconds after the starter switch is activated.
 
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To make the Ballinger display on the SDS control head, it had to be set to the 'Extreme range (gas)', the SDS O2 sensor input has to be set to 'AEM (new)' format. AFR display values on both units are not exactly same but within a couple tenths of each other, example 15.2 on Ballenger vs 15.3 showing on the SDS. Close enough for me.
Basically my ignition is set at 25btdc and varies with MAP and RPM ranges, it may retard up to 4 deg or advance up to 4 deg dependent on rpm & load.
Additionally, the Lean Of Peak switch on the SDS advances the timing 5 deg. more than the reactive time described above. The Lean Of Peak switch also leans out the basic fuel map by 26% to give me the 15 - 16 AFR for reduced fuel flow and maintaining reasonable temp changes and power loss. The AFR will still vary a bit as the fuel map is also influenced by the Air Temp, Engine Temp & MAP.
In general High load situations would drag the AFR to around 11.6 - 12 with timing at around 24btdc. In lean conditions I would see AFR about 15.5 - 16 and timing about 33btdc. These would be the intended program parameters I want in the SDS & I still have the lean mixture knob (which I rarely touch anymore) if I want to play with it.

Part of our Ballinger experiment, I power it through a delay relay to see how it affects the life span of the NTK sensor. Power is delayed 30 seconds after the starter switch is activated.

I'm still using my mix knob to control my mix entirely manually and using LOP button just for +4 degrees timing - but after more than 100 hours on the system now I am comfortable with it and will soon program the fuel cut and leave the mix knob alone, and start fine-tuning the fuel map using the AFR.
 
To make the Ballinger display on the SDS control head, it had to be set to the 'Extreme range (gas)', the SDS O2 sensor input has to be set to 'AEM (new)' format. AFR display values on both units are not exactly same but within a couple tenths of each other, example 15.2 on Ballenger vs 15.3 showing on the SDS.

Ralph - I'm not quite understanding the reason for the Extreme range vs. the Standard range. Is the Extreme range needed because you expect to operate outside the 9 to 16 AFR range provided by the Standard setting? My understanding is that 9 is way too rich. With 16 AFR being around 50F LoP, I could understand possibly wanting more range on the lean end.

Extreme gives you a 14-point AFR range vs. 7 points for Standard, but at the cost of sensitivity. A 1.0v change in the A/D output from the Ballenger is 1.4 AFR in Standard or 2.8 AFR in Extreme.

I'm building an Arduino-based closed-loop mixture controller using the Ballenger box & a linear servo to push-pull the mixture knob. I'm trying to decide how many presets I need, two or three. RoP, LoP, and maybe Takeoff. Thus my question about AFR values during takeoff. It sounds like a small detail, but the answer changes the switchology required, and thus my panel layout.

Thanks!
David
 
Good luck with your Adrino system, sounds interesting, sounds like a lot of work!

The reason for me using the extreme scale was to adapt the Ballenger output to read on my SDS panel control head. It also came in handy during testing & setup as I did explore leaning values higher than those I decided to be safe and workable for me.
In my case, displaying the AFR is 'displaying the result' of the SDS EI/EFI tuning. It is not used as a controlling factor in the running of the engine as in 'closed loop' systems. The SDS (Aviation) system use OAT/TPS/RPM/MAP/CHT data to run the engine.
Ross has a chart on his website that shows general AFR ratios to power output that might help you, but AFR is only part of the operating story.
 
Price Increase in 2021

We'll be implementing a 3% price increase effective Jan. 1/21 to cover an increase in aluminum billet and other parts prices we've had from vendors over the last year plus we've been supplying a few extra bits in the kits which we hadn't been charging for.

For early 2021, we'll be coming out with some new parts to make installation easier for vertical induction engines.

Our system time to build is sitting at about 2 weeks right now on EM-5 systems, about 7 days on CPI-2 and 4 days on CPI.
 
Holiday Hours

We'll be closed Dec. 24-27. Open 28-30. Closed 31st for inventory.

Closed Jan. 1-3 and ready to roll again Jan. 4.

We have an order backlog stretching into the first week in January plus many of our suppliers aren't open much during the next 10 days either.

Thank you to all our customers who've chosen SDS products. We really appreciate your support. Thank you also for your feedback to improve our offerings. There will be more new stuff coming down the pipeline in 2021.

Happy holidays and may the best of health be with you.

Be sure to get flying if you can- that is our temporary escape from the worldly problems and stress we face on the ground these days. :)
 
David and Ralph,

Here's another few data points on STD vs Ext range on the Ballenger:

I started using the AFR400V1 when it was the only choice. I found that when leaning on X-Cs, I could lean past where the AFR held at 16.0. I conducted a lot of tests to balance my injectors, for which the STD is fine...peak is in that 14.7-15.0 range, and I was fine tuning the injectors with EGT and FF, not with AFR. But these tests were a pretty solid validation that the AFR works well...peak was very close to book stoichiometric values. I also tested well into the LOP range, to see when speed fell off, and when the cylinders began to run a bit rough. Again, the primary references were EGT and FF, and with the AFR400V1, the readout was a solid 16.0 for several turns of the mixture, so it was no longer providing any additional test detail or data.

When the V2 came out, I bought it, and moved the V1 to a racing Glasair, replacing a failed system in that plane (different mfgr). Noting that the V2 does have lower sensitivity in Ext mode, I wondered if the reading would jump around more in that mode. After many tests...its hard to say...maybe a bit. But I am now able to read AFRs above 16.0 as I lean, and with balanced injectors, have leaned into the 17s and 18s before rough running occurs. Speed does drop off significantly there too.

I typically run in the high 15s (15.5 to touching 16 occasionally), which is usually a bit less than 50 LOP. Good power and speed, cool CHTs, lower FF than ROP, for sure. After all this testing, given where I run, the STD mode would likely be sufficient. However, if you want to explore the fringes of LOP and see where AFR is, the EXT mode is pretty effective.

Ralph, have you noted more jumping in the numbers in EXT mode?

David, good luck with your closed loop mixture controller. It will be interesting to see the results. Will it use AFR to set the mixture? If so, you may need to dampen the slightly fluctuating readouts. As for Takeoff AFRs, during Reno Racing, Andy (SDS user and our current Sport champ) and I discussed takeoff AFR. I had my AFR 400 V1 on a TIO-580 with 2 mags, standard FI and mixture control, and an automatic waste gate. We both used an AFR of about 10 to provide plenty of cooling. Neither of us was running anything close to full throttle on takeoff or climb, to keep temps low till we were in the chute and racing. In my RV (IO-540, standard FI, 1 mag, 1 EI), full rich sea level takeoffs are in the 10s, and up in Reno, I'll lean to high 9s low 10s. I've seen 8s if I had the mixture in too far, and then corrected. Ran fine, but its not a very efficient place to run.

Hope those numbers give you some data to work with. With that closed loop system, are you trying to replicate the magic that Ross has in his SDS? I'm sure you've thought of this, but be careful how lean you allow the linear actuator to pull the mixture at high power. ;) Cool project tho.

Someday Ralph and Bill are gonna make me a Ross SDS guy too...just a few projects in the mill ahead of that! :D

Cheers,
Bob

Ralph - I'm not quite understanding the reason for the Extreme range vs. the Standard range. Is the Extreme range needed because you expect to operate outside the 9 to 16 AFR range provided by the Standard setting? My understanding is that 9 is way too rich. With 16 AFR being around 50F LoP, I could understand possibly wanting more range on the lean end.

Extreme gives you a 14-point AFR range vs. 7 points for Standard, but at the cost of sensitivity. A 1.0v change in the A/D output from the Ballenger is 1.4 AFR in Standard or 2.8 AFR in Extreme.

I'm building an Arduino-based closed-loop mixture controller using the Ballenger box & a linear servo to push-pull the mixture knob. I'm trying to decide how many presets I need, two or three. RoP, LoP, and maybe Takeoff. Thus my question about AFR values during takeoff. It sounds like a small detail, but the answer changes the switchology required, and thus my panel layout.

Thanks!
David

Good luck with your Adrino system, sounds interesting, sounds like a lot of work!

The reason for me using the extreme scale was to adapt the Ballenger output to read on my SDS panel control head. It also came in handy during testing & setup as I did explore leaning values higher than those I decided to be safe and workable for me.
In my case, displaying the AFR is 'displaying the result' of the SDS EI/EFI tuning. It is not used as a controlling factor in the running of the engine as in 'closed loop' systems. The SDS (Aviation) system use OAT/TPS/RPM/MAP/CHT data to run the engine.
Ross has a chart on his website that shows general AFR ratios to power output that might help you, but AFR is only part of the operating story.
 
Hey Bob!
You developed a Texas twang yet?

I was getting an AFR jumping reading in both normal & ext modes with the Ballenger & AEM systems but found out was being caused by a flaky OAT temp sensor wiring connector that was causing havok with the RPM/Fuel map. Generally I sense that as the old Bosch 4.9 sensor in the AEM system was giving me leaner readings than the new Ballenger setup is now reporting, basically fooling myself that I was running leaner than I actually was. Maybe I can stretch my LOP settings further towards the 17 to 18 AFR ranges in the future, I've been settling for the 16+ range for now.
Nice thing about my current settings is that I can instantly loose a gallon per hour now without notable drop in power & NO temp changes!
Life is good, kinda.

Seasons Greatings to your bunch!
 
Ralph,

My AFR bounces around in a manner very similar to what I saw in your video with Ross. I basically mentally average out the numbers to estimate what the AFR is. Seems plenty good for normal ops, and I still stay well rich of peak for racing. In Reno, my CHTs will start to get hot if I run leaner than about 11. By hot, I mean over 400-405...so "conservative hot", in racing terms. ;) Hoping the new AFP servo will let us run closer to best power (12.5). Might add water on the cylinders too, to see if we can lean to a bit more power.

It would be great if we could dial in a steady AFR with the Ballenger (or any other), but I wonder if a single sensor in the left pipe can do that...I figure its getting exhaust from 2, 4 and 6, and the exhaust AFR might actually fluctuate a bit given that. With balanced injectors, they should be pretty close to each other in terms of AFR, but each is a different distance from the sensor. Of course, the exhaust pulses are extremely fast, so I'm just not sure. Ross, perhaps you may have some thoughts on that.

I'm with you on the benefits. For me, ROP to LOP leaning (say best power to hi 15s) drops FF about 2 gph, with little change in speed. Going into the 16s and 17s results in a speed loss, and into the 17s to 18s into very low CHTs (sometimes <300), an audible roughness in the motor, and a pretty marked decrease in speed. After that it gets pretty quiet :p

Merry Christmas Amigo, and tell that Great Scot howdy for me. I may have said Y'all once or twice, but fixin' hasn't crept in yet...well, except when I'm fixin' the plane! :D

Cheers,
Bob
 
Happy New Years to everyone and thank you for your support in 2020.:)

We are booked up through to the 3rd week in Jan. now so please be patient if you've recently ordered.

Closed on the 31st for inventory, back to it on Jan. 4.
 
Happy New Years to everyone and thank you for your support in 2020.:)

We are booked up through to the 3rd week in Jan. now so please be patient if you've recently ordered.

Closed on the 31st for inventory, back to it on Jan. 4.

Happy New Year, Ross!

Looking forward to getting my Engine with ECUs from Darren at Aerosport in early 2021!
 
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