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SDS EFI in 2023

Basically you can set an AFR target at each rpm range. You can also set a LOP AFR target.

Closed loop is boxed in by MAP and RPM high and low limits as well. Go outside any one of those and it drops back into open loop (runs off programmed values as before).

As I mentioned in in another thread, this is mainly aimed for those using unleaded avgas or mogas. We have an NTK sensor on Les' RV-10 now, will see what the life is like on 100LL eventually. Maybe it's workable. The NTK is rumoured to tolerate lead better than the Bosch sensor. He has his sensor mounted on an extended boss which may help keep lead off of the sensor.

As a point of interest on the test flight today, peak EGT occurred at about 15.1 AFR on the wideband, right where expected on 100LL.
 
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Bosch sensor not NTK

What should the AFR be at the desirable LOP fuel flow? I ran LOP via the programmer switch yesterday for the first time. I had set -35% AND 6 degrees advance and was seeing 16.5-16.8 AFR. Engine ran pretty smooth but still required a little adjustment to a couple of cylinder trims.

Unfortunately, my Bosch (not NTK) sensor does not work at higher power settings (AFR less than about 12 or so).
 
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What should the AFR be at the desirable LOP fuel flow? I ran LOP via the programmer switch yesterday for the first time. I had set -35% AND 6 degrees advance and was seeing 16.5-16.8 AFR. Engine ran pretty smooth but still required a little adjustment to a couple of cylinder trims.

Unfortunately, my NTK sensor does not work at higher power settings (AFR less than about 12 or so).

In testing on Les' plane, we were able to see AFRs from about high 9s to 17 with the NTK. I'll have to review the logs when I have time. In the past, we've found around 16-16.5 AFR corresponds to around 30-40 deg LOP which should be best economy. We've leaned as far as 18 to 1 AFR but while FF is impressively low, the speed takes a bigger hit and MPG is less.
 
In testing on Les' plane, we were able to see AFRs from about high 9s to 17 with the NTK. I'll have to review the logs when I have time. In the past, we've found around 16-16.5 AFR corresponds to around 30-40 deg LOP which should be best economy. We've leaned as far as 18 to 1 AFR but while FF is impressively low, the speed takes a bigger hit and MPG is less.

Agreed, the 16-16.5 range is right where I set mine for XC cruise at altitude.
 
16----16.5 and add 3* timing seems to work well for me. I have run the RPM down pretty low, 1900 rpm and WOT and the engine is still smooth and seemingly happy. 5/5.1 GPH at that RPM.

IO320 with C/S in a high wing tri gear with 22" tires and no wheel pants.
 
I guess over time I’ve gotten somewhat away from focusing on LOP and AFR’s in favor of adjusting the mixture to dial in fuel flow to determining where the mixture should be. Once at altitude the first thing I do is pull the prop back to 2200 RPM’s. I know most people run their engine at 2400 RPM’s but my typical cruise is at 2200. At this RPM and at 10-12k feet, I’m typically well below 65% power, so no damage can be done if running at peak. I then make minor adjustments and set the mixture to a F.F. of 8.5 GPH. At these altitudes, RPM’s, F.F. and WOT, I’m typically at peak or just a touch LOP with AFR in the mid 14 range. Everything seems to be very happy there and usually gives me a cruise speed of right around 165 kts. TAS. I can certainly lean from there if I want to, but my speed really starts to suffer. So, bang for the buck, my parameters work well for me.
 
Documentation Release

I'm back after a few days off.

We should finally be finished the EM-6 installation manual on June 12 and will upload to the aircraft page at that time.

It's been expanded and clarified greatly, incorporating several previously separate documents into one main one. We've taken many customer suggestions into consideration. This is always a work in progress as we gain more feedback and add new features over time.

We've already started to supply some EM-6 bits to waiting customers to keep their builds going and the first full kits from the huge order backlog are being built now.

Sorry for the long wait, we wanted to make this as good as we can before release.

I'll try to get a short vid done before the 3rd week of this month, with an overview of the main new features.
 
Finally Pulling the Trigger

Today, 30 days after the first flight of the EM-6, we are finally ready to start supplying EM-6 ECUs and kits, the fist of which will ship later this week.

Here is a link to the new EM-6 aviation manual: http://sdsefi.com/em6acman1.pdf

Expect some frequent revisions initially as we have time to shoot some better photos to replace some re-used, grainy ones plus improved charts and diagrams.

We are concentrating on production for the next few weeks.

Thanks to everyone for their patience, this has been a long time in the making.
 
Congrats Ross. I know you and Barry have worked long hours for years now on EM-6. Looking forward to the improvements and especially closed loop with unleaded fuel.

I really like your dual bus 6 cylinder wiring topography. Mine has been flawless so far.
 
RV-10 Info Link

Les Kearney continues to add valuable content to his site for RV-10 builders: https://rv10.ca/

This is a great resource and especially so for those building RV-10s with SDS.
 
Fuel Filter SB

I just posted a SB on fuel filter contamination on the Aircraft Page too with some guidance on the subject as covered in the thread here a few weeks back.

Appreciate any findings and photos from customers when they inspect their filters to help better understand what may be going on here.
 
I just posted a SB on fuel filter contamination on the Aircraft Page too with some guidance on the subject as covered in the thread here a few weeks back.

Appreciate any findings and photos from customers when they inspect their filters to help better understand what may be going on here.

Tried and failed to find it - link?
 
RV10 Dual ECU Dual Bus System

Curious what most RV10 builders are opting for now in terms of the electrical dual bus/dual ECU electrical system build?

Reading thru the new manual:

"Dual Power Buss means that normally both busses are powered on all the time and both ECU’s are running all the time when the engine is running. Both Busses each have their own alternator and battery.
Power Buss A powers the Primary ECU & injectors 1,2,3 and Power Buss B powers the Backup ECU & injectors 4,5,6. Each Buss powers an ignition coil pack on systems doing ignition control. "

then later....

"Backup Electrical Power Considerations
Electrical power is necessary to keep the ECU, fuel pump, coils and injectors running so it’s important to think about having a backup power source available. In the case of Lycoming engines, a small backup alternator like the Monkworkz MZ-30L, B&C SD8, SD20 or BC410-H SD can be fitted to a vacuum pump pad. On other engines, a small second alternator could be fitted.
If you don’t have a second alternator, you should have a small backup battery."

My question: Are RV10 Dual Bus/Dual ECU builders opting for 2 alternators and 2 batteries supplying the separate buses? With the advent of the Monkworkz I am wondering if a dual ECU system could be supplied with a dual battery/dual bus/monkworkz running shadow over the whole thing?
 
I'd estimate that around 75-80% of RV-10 builders with SDS are opting for a single bus layout with either dual alternator and/or dual batteries.

The rest are going dual bus, again with dual alternators and/or batteries.

Lots of differences in ideas on the electrical architecture.

The most important requirement in my view is to be able to isolate primary power from backup power, otherwise shorts or over voltage conditions could take out both systems.
 
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One implementation

Our implementation of this architecture requires two separate, independent electrical systems running full time. We use B&C alternators - one belt driven, the other pad mounted. I don’t know if the Monkworx is designed for continuous use. We don’t have a “backup” alternator, as either bus can (and does) run its respective ECU, fuel pump and coil pack. With the modified relay box, you can switch injector power from split (normal) mode (1,2,3 to one bus, 4,5,6 to the other) to all on one.

Complete loss of one electrical system results in the loss of one ECU, fuel pump and one coil pack. The remaining ECU triggers all injectors (by selecting PRI or BAK) via lever lock Honeywell switch.

We do have a cross-tie contactor that we only use for engine start. All SDS components are individually protected by circuit breakers and powered from one of two hot battery busses. Very happy with the system and the redundancy of electrical power,
 
Filter change

Curious what most RV10 builders are opting for now in terms of the electrical dual bus/dual ECU electrical system build?

Reading thru the new manual:

"Dual Power Buss means that normally both busses are powered on all the time and both ECU’s are running all the time when the engine is running. Both Busses each have their own alternator and battery.
Power Buss A powers the Primary ECU & injectors 1,2,3 and Power Buss B powers the Backup ECU & injectors 4,5,6. Each Buss powers an ignition coil pack on systems doing ignition control. "

then later....

"Backup Electrical Power Considerations
Electrical power is necessary to keep the ECU, fuel pump, coils and injectors running so it’s important to think about having a backup power source available. In the case of Lycoming engines, a small backup alternator like the Monkworkz MZ-30L, B&C SD8, SD20 or BC410-H SD can be fitted to a vacuum pump pad. On other engines, a small second alternator could be fitted.
If you don’t have a second alternator, you should have a small backup battery."

My question: Are RV10 Dual Bus/Dual ECU builders opting for 2 alternators and 2 batteries supplying the separate buses? With the advent of the Monkworkz I am wondering if a dual ECU system could be supplied with a dual battery/dual bus/monkworkz running shadow over the whole thing?

Monkworkz MZ-30L, B&C SD8, SD20 or BC410-H SD, add to that BC462-H Alternator, 35-60 Amps which is a little larger (And heavier) but all good alternatives. Any of these can run "shadowing" the primary alternator. I am not sure what others are doing but my primary bus and engine bus are completely independent and monitor each bus voltage and alternator output. I have added a manual "crosstie" which if selected my pad mount alternator (Engine bus) can power the primary bus. (I might need to do some load shedding so want it to be a manual operation) With current pad mount alternators capable of outputting 30 amps or more and avionics capable of letting us know almost within seconds if we lost an alternator, we have a fairly robust energy dependent engine system. I am not an optimist but seems small independent back-up battery systems might be more trouble than they are worth.

Over the weekend changed filters, 75-micron pre-filter virtually spotless and 10-micron post filter has some small black fines in it. (Less than 10 micron) Measured pressure drop and almost nothing. 250 hrs. on filters.
 
An additional SDS advantage

Given that SDS uses two six cylinder coil packs, this makes it easy to have truly independent busses with one ECU, fuel pump and coil pack on a single bus.

Don't know how you would do this with a system that uses three coil packs for a six cylinder engine (without diodes or additional relays).
 
I'd estimate that around 75-80% of RV-10 builders with SDS are opting for a single bus layout with either dual alternator and/or dual batteries.

The rest are going dual bus, again with dual alternators and/or batteries.

Lots of differences in ideas on the electrical architecture.

The most important requirement in my view is to be able to isolate primary power from backup power, otherwise shorts or over voltage conditions could take out both systems.

Thanks Ross - Appreciate you clarifying this.

So are the 75-80% RV10 builders opting for single Buss doing the dual ECU system as well?

Thanks all for helping me wrap my brain around this stuff.
 
I'd say something like 95% of RV guys are doing dual ECUs and something close to 100% of RV-10 guys are fitting dual ECUs. Having the cylinder trim capability and redundancy is a priority for -10 owners it would seem.
 
ECU Re-flash

I've had a few people ask about how the user re-flash works on the EM-6.

This is done through the ECU data port which normally connects to the card logger now.

You download SDSDASH to your laptop from a link we provide. This is the logging, communication and de-encryption software allowing the EM-6 to talk to your Windows device.

We'll send you a file by email for each ECU which contains an encrypted file matching each ECU's burn # (you can see that # info on your programmer on power up).

Open SDSDASH, Click on the Reflash Upgrade button.

Find the file on your laptop.

Click on Begin Reflash button.

Progress bar will show status of reflash process. Takes around 100 seconds to complete.

Done.
 

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I know the 4 cylinder version works a little bit differently than the 6 cylinder version. Is there a good way to have dual busses powering a dual ECU 4-cylinder EM-6?
 
I know the 4 cylinder version works a little bit differently than the 6 cylinder version. Is there a good way to have dual busses powering a dual ECU 4-cylinder EM-6?

Could possibly use a 6 cylinder relay box. I'd have to look at that. Never had anyone do that yet.
 
3rd Manual Update

Just uploaded the 3rd EM-6 manual revision. Some improved schematic diagrams to replace the previous photos.

To those who received EFI kits without ECUs, ordered after April 15th or so, we should be shipping you EM-6 ECUs and data logging modules later this week.
 
Hey Ross

Few questions for your or Barry.

I am running the dual CPU EM5 on my RV10, have just over 300 hours, I am very satisfied with EM5 and not sure I will pursue the upgrade path to EM6. (I am getting lazy and EM5 is running great)



My current flight mode is pretty simple and very low work load., after climb out, I set prop at 2400 RPM, pull power back to 60% (if necessary) and flip "LOP" switch. I typically do not touch anything again (other than throttle) until taxing. I have found for instrument approaches, the RV10 climb gradient on a missed approach is too steep if I go to 2700 RPM so I simply leave it a 2400 RPM for approach.


Few misc questions\comments:

- Is the data acquisition module backward compatible to EM5 units? This module would make it much easier to capture data vs having my laptop sitting on open seat with cable to back of ECU case.

- Is there a method to feed the AFR signal directly into a Dynon HDx input? When performing tuning or gathering performance data it is a bit cumbersome to match the EGT data with AFR data as they are in separate software programs.

- On the EM6, using closed loop tuning mode, what happens if\when the AFR sensor fails?

- It would be good to have a repository of SDS ECU values on your website of various folks with their engine configurations (along with the fuel type). I have swapped data sheets with Les several times and it has been very helpful.

(My wife & I just spent two months in 4 wheeled version of RV touring eastern part of your beautiful country. (Nova Scotia and PEI) So glad the borders are back open!

Steve
 
steve murray

- Is the data acquisition module backward compatible to EM5 units? This module would make it much easier to capture data vs having my laptop sitting on open seat with cable to back of ECU case.

- Is there a method to feed the AFR signal directly into a Dynon HDx input? When performing tuning or gathering performance data it is a bit cumbersome to match the EGT data with AFR data as they are in separate software programs.

- On the EM6, using closed loop tuning mode, what happens if\when the AFR sensor fails?

- It would be good to have a repository of SDS ECU values on your website of various folks with their engine configurations (along with the fuel type). I have swapped data sheets with Les several times and it has been very helpful.

Steve

Steve,

The card logger isn't backwards compatible with the EM-5 ECUs.

You should be able to Y off the wideband linear output signal to the Dynon and display the 0-5V signal as AFR.

If the wideband fails, the ECU will jump out of closed loop, back into open loop and put on the Fault light in the programmer. We're not so keen to have people use the closed loop feature with 100LL as we've seen such a big variation in sensor life. It was really intended for Mogas and unleaded Avgas.

A web page with standard engine maps is a great idea. We'll try to get something up over the next couple months, time permitting.

I suspect some people will stay with their EM-5s for a while, at least until UL Avgas is more widely available. Les Kearney operates much like you and with the EM-6, is flying it like the EM-5, not using closed loop.
 
EM-6 Manual Update

Just did another manual update (new links on Aircraft Page), fixing some typos, adding some additional text and info plus including the drawings for the panel cutouts for the programmer and card logger module in there.

For those doing panels for an EM-6, be sure to look at the new charts on breakers and switches so you don't forget anything. There are a few changes from the EM-5.

Direct manual link here: http://www.sdsefi.com/em6acman9.pdf

We don't plan to include paper copies of the manual any more with EM-6 kit orders as there may be revisions by the time some folks are installing the system plus the manual is 77 pages now and a digital document is easier to search. Helps to keep costs down a bit too.
 
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Website Update

Over the last 2 days, I've done extensive re-arranging and cleaning up of the Aircraft Page as well as many linked sub pages.

Deleted many obsolete photos and replaced with current ones.

Created some new pages to move older or less relevant content off the Aircraft Page to de-clutter it more.

Have a separate Service Bulletin Page now, linked from Aircraft Page.

Now have a long overdue Maintenance and Inspection Schedule published.

The EM-6 manual has a 7th revision now, adding some more dimensions and drawings for mounting components.

Vacations put a damper on kit deliveries last week, we should be getting back to normal starting tomorrow on that front.
 
Just did another manual update (new links on Aircraft Page), fixing some typos, adding some additional text and info plus including the drawings for the panel cutouts for the programmer and card logger module in there.

For those doing panels for an EM-6, be sure to look at the new charts on breakers and switches so you don't forget anything. There are a few changes from the EM-5.

Direct manual link here: http://www.sdsefi.com/em6acman4.pdf

We don't plan to include paper copies of the manual any more with EM-6 kit orders as there may be revisions by the time some folks are installing the system plus the manual is 77 pages now and a digital document is easier to search. Helps to keep costs down a bit too.

Direct link is giving me a file not found error.
 
Oshkosh

For those wanting to talk to someone about SDS, Les Kearney will be at Osh again this year with his RV-10 with the latest EM-6 installed. He's very knowledgeable about the system and you can see it all in the flesh.

Les' plane is the one we use to make the RV-10 videos and do EM-6 6 cylinder testing on. He also has the full Garmin G3X suite and knows a bunch about that as well.

PM or E-mail me and I'll pass along his phone number so you can arrange a time to talk.

We never seem to have the time to attend as we're always snowed under with orders and have to keep that moving. Even more so this year. Another reason is the EAA just isn't too friendly to small business any more with costs and insurance requirements.

Anyway, often better to talk to a user directly than the vendor.

We may have some other customers at Osh. If they contact me and give the ok, I'll try to put you in touch.
 
Hey Ross

I am happy to discuss my implementation on my RV10 if anyone at Osh has questions. I will be up here few more days. I sent you my cell # via PM.

Steve Murray
 
-14A with SDS

Ivan Kristensen is at Osh in HBC Row 323 with his very clean -14A. Is happy to chat with people about the system and AFS panel.
 

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Airventure Cup Race

SDS was well represented at the race this year:

1st place Unlimited Andy Findlay
1st place Sport Joe Coraggio
1st place RV Gold Dave Anders

Dave was the fastest 4 cylinder RV again as he has been several years past.

Andy beat the turbines and was the fastest overall.

Congrats to all!
 
Reno

With Osh over, we are prepping some EM-6s and card logger modules for some of the racers this month.

I plan to attend this year for the finale if things work out.

Hoping all the Sport Class engines hang together this year and we get to see some great racing. :):cool:

If you haven't been to Reno, this is your last chance to experience this amazing place and event.
 
Hard Cold Starting

We received feedback on this a few times so thought I'd comment.

We have found that many complaining of this don't have the fuel pump switched on before the ECUs are powered up.

Why is this important?

As the ECUs are powered up, they initiate a short squirt of fuel below a certain engine temp to aid starting. You get no fuel injected without fuel pressure. Secondly, if you use the throttle pump-to-prime feature, you also get nothing out of the injectors without fuel pressure.

If your switchology doesn't permit pumps on before ECUs, suggest you power up, switch the pumps on until you see fuel pressure, switches off, switches on again, then crank. The regulator should hold fuel pressure for at least 30-60 seconds.

Most engines will tolerate being very rich for cold start but they won't fire up when lean.

The Start Values control the amount of fuel injected during cranking and the first few seconds after engine start. Start Cycles controls the number of injection cycles that the Start Values last for (usually about 3-8 seconds). Once these time out, the ECU reverts to Engine Temp Values for the rest of the warm up cycle.

Start Cycles are typically set at around 12-20 for 4 cylinder engines and 20-30 for 6 cylinder engines.
 
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If your switchology doesn't permit pumps on before ECUs, suggest you power up, switch the pumps on until you see fuel pressure, switches off, switches on again, then crank. The regulator should hold fuel pressure for at least 30-60 seconds.

Ross, I think your EM-6 manual talks about not needing a switch for the ECUs and they can come on with the master/engine busses. Your post would seem to suggest that the pump switches should be on before you turn the master/engine bus switch on then?
 
Most people are skipping the separate ECU power switches and having them come on with the master (breakered of course).

I just bring this to peoples attention that they may have to change their cold starting procedure as outlined below.

We will investigate a software change to wait 2-3 seconds after ECU powers up before initiating the cold injector squirts to give you time to get the pumps on and fuel pressure.
 
Ross, was hoping I could pick your brain for a minute. I can't figure out what to try next to make the plane start better when cold. I've tried changing the cold start enrichment to both richer and leaner with no effect. I'll do this by seeing what the engine temp is reading before start, then changing the enrichment percent at that temp before crank. I've tried cycling the throttle with the pump on from 1 to 5 times. Nothing seems to change cold start behavior. I have to crank for 3-5 seconds and it never even tries to start. I'll let off the starter for a break, and on try number 2 the engine fires in less than a blade. Hot starts it fires up first try in 1-2 blades.
 
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Ross, was hoping I could pick your brain for a minute. I can't figure out what to try next to make the plane start better when cold. I've tried changing the cold start enrichment to both richer and leaner with no effect. I'll do this by seeing what the engine temp is reading before start, then changing the enrichment percent at that temp before crank. I've tried cycling the throttle with the pump on from 1 to 5 times. Nothing seems to change cold start behavior. I have to crank for 3-5 seconds and it never even tries to start. I'll let off the starter for a break, and on try number 2 the engine fires in less than a blade. Hot starts it fires up first try in 1-2 blades.

Would be sure you have fuel pressure before the ECUs come on. You may have to cycle power and pumps as previously described. No FP, no prime. Your resting technique success makes it high probable that there is no FP prior to ECU power up.

Let me know if this helps.

3 seconds of cold cranking is pretty normal, about what my Subaru takes. The Lycoming has very large cylinders so takes a lot of fuel for the AFR to reach the required 4-6 to 1 to cold start.
 
I just bring this to peoples attention that they may have to change their cold starting procedure as outlined below.

We will investigate a software change to wait 2-3 seconds after ECU powers up before initiating the cold injector squirts to give you time to get the pumps on and fuel pressure.

The software delay seems like a very good idea. For many users the whole point of an EFI installation is to eliminate specific pilot procedure. They want it to crank like their car.

Those of us who can rub our bellies and pat our heads at the same time are perfectly happy with constant flow injection ;)
 
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