We have been supplying the experimental aviation market with engine management systems since 1994. We offer aviation specific software and hardware for popular experimental engines and we fly what we sell. We are involved with several kit manufactuers and alternative engine suppliers in joint R&D programs and in product supply.

We have provided systems for 3 cylinder Metro engines, 4 and 6 cylinder Suzuki, Continental, Lycoming, Franklin, Jabiru, Rotax, Saturn, Subaru EJ22, EJ25, EG33, EA82, EZ30, EZ36, Rotorway, Toyota, Hirth, Honda, Rover/ Buick and Mazda engines. These have accumulated over 100,000 flight hours on hundreds of aircraft and military UAVs all over the world in the last 19 years. Land based systems have accumulated an estimated 24 million hours of operation under widely varied and sometimes severe conditions. We are currently flying an RV6A powered by a turbocharged Subaru EJ22 engine for product development purposes and now constructing an RV10 to be powered by a twin turbo Subaru EG33 engine for further testing and development of our aviation products. We were the first to have a Gold Championship win at the Reno Air Races with EFI in 2010.

Turbo Subaru powered RV6A and RV7. Both equipped with SDS EM-4 engine management systems

http://www.youtube.com/watch?v=B940-zuZI3k
Turbo Subaru RVs in formation

http://www.youtube.com/watch?v=kjNsbU6nFAw

http://www.youtube.com/watch?v=44HbwRm8lHw

http://www.youtube.com/watch?v=bOTmwnhGy6A

http://www.youtube.com/watch?v=4i6W-nTPbZo

Here is a takeoff video of Randy Crother's Turbo STI Subaru powered RV7A. SDS EM-4 4F equipped: http://www.youtube.com/watch?v=om1GUJ5m1nY&feature=channel_page


Disclaimer

This product does not conform to any recognized set of standards or certifications for aviation applications.

This ECU is not waterproof and will not function as designed if moisture invades the enclosure or power/ ground connections are interrupted. Failure of this unit may result in a complete loss of engine power.

Use of this product on amateur built/ experimental aircraft is at the discretion of the buyer who accepts full responsibility for any consequences resulting from its use. Since Racetech Inc. cannot control the installation, programming, application environment or use of its products, we accept no responsibility for damage, loss or personal injury resulting from the use of SDS products. By using SDS products, the user understands and accepts this.

If any user does not agree to this disclaimer, they may return the system in new condition for a full refund.



Basic components of distributorless EM-5 4F system shown with billet coil pack


Photo of aircraft 3 1/8 panel mount display head (backlit). With V17 software, has 4 gauge modes to display, manifold pressure, rpm, engine temperature, induction temperature, battery voltage, fuel flow, injector duty cycle, throttle position, acceleration enrichment, mixture knob position, ignition timing and O2 sensor voltage. Also displays error codes for sensor failures, check engine light feature and allows full programming of the system in flight.


Advantages of SDS Over OE EFI Systems in Aircraft

While there are many automotive engined homebuilt aircraft flying with the OE computer controlling fuel and ignition successfully, many users may not be aware of some potential pitfalls of using these systems. Many OE computers can either shut off the injectors if certain things fail such as a water temperature sensor to protect the engine from a perceived or real overheating condition or go into a very low power limp home mode. Either of these scenerios mean that you are coming down in an aircraft. The designers of these automotive ECUs did not take aircraft use into account during the design phase obviously. Their considerations were likely as follows, in order of importance: 1. Reliability- keep the engine from destructing ( shut the injectors off if necessary), 2. Emissions, 3. Fuel economy, 4. Driveability, 5. Power. Fortunately modern EFI systems, sensors and ECUs are VERY reliable. Just be aware, that as on your Continental or Lycoming, anything CAN fail equally so on your automotive/EFI conversion, making you an unwilling glider pilot.

Many people have spent countless hours trying to unravel programming code on OE ECUs for use on aviation applications, to undo unsuitable code or responses or security interlocks sometimes successfully, sometimes not. Others wonder what the ECU might do when certain sensors or inputs are modified or disconnected. What some people have attempted to do in dozens or hundreds of hours with often unknown consequences using OE ECUs can generally be done in minutes with SDS. You know exactly what the system will do without any hidden secrets or repercussions. All OE ECUs were designed to use an O2 sensor for closed loop feedback of the air/ fuel ratios at part throttle. As such, they may not be very suitable for use with leaded avgas. SDS does not require an O2 sensor at all.

Disadvantages of SDS vs. Conventional Aircraft Engine Systems

The big disadvantage of EFI compared to a carb or mechanical injection and magnetos is that electrical power is required for the pump, computer, ignition and injectors. The likelihood of both the alternator and battery failing simultaneously is practically zero with standard aircraft maintenance procedures. Generally, a good battery will allow you to keep essentials powered for 20-90 minutes after an alternator failure permitting diversion to another airport. We consider proper gauges and/or warning lights to indicate an alternator failure to be very important. We have an ammeter, voltmeter, low voltage warning light and buzzer now on our RV6A and also added a backup battery in Feb. 2005.

Advantages of SDS vs. Conventional Aircraft Engine Systems

Virtually zero maintenance, lower fuel flows due to better mixture distribution, automatic mixture control, no carb heat, smoother running, no mag checks, no live mag issues, longer engine life due to proper mixture control and less bore washing are some of the major benefits of EFI.

Why should I consider SDS over other brands of EFI for my aircraft?

1. We have more experience than any other company in this field with an unmatched track record on many diffrent engine types including the 2010 Super Sport Reno Gold Championship winner.
2. Our basic designs are also used in automotive applications so we have a huge amount more hours and customer feedback to quantify reliability than aviation only sytems.
3. We fly what we sell and are actively involved with the aviation market.
4. Our systems are designed to keep the engine running at close to full power even with multiple sensor failures unlike many other systems which may shut the engine down or OEM systems which will go into a limp mode, not allowing enough power to maintain flight.
5. We have the best tech and customer support in the industry.


Quick Aviation Q&A

Q. What about redundancy?
A. SDS does not offer redundancy in the aviation systems that we offer. Our thought is that the extra wires and switchgear required to isolate all potential faults makes it more likely to have a failure of both systems. On twin plug engines, it is posible to retain one mag and add a fuel nozzle into the plenum as a backup. For pilots who are not comfortable with this idea, there are other systems to choose from on the market which might better suit your needs- including magnetos and carburetors.

Q. Are the aviation units any different from the automotive ones?
A. SDS was conceived as an automotive system so most of the components are identical. The advantage of this compared to units developed specifically for aviation is that we have accumulated several million hours of operation due to the greater numbers in automotive service where conditions are usually more severe. Hardware differences would be things like the Hall Effect sensors used on aviation systems comply to a higher temperature spec than the automotive ones and the aviation programmer is different to be able to be panel mounted. Minor software differences include MAP calibration in inches of Mercury absolute and special programmed defaults to help minimize the effects of sensor failures.

Q. What use is the mixture knob on an automatic aviation system?
A. We recommend the mixture knob be panel mounted in all aircraft to allow the pilot to make a mixture adjustment in case of certain sensor failures. This gives you independent control of the mixture from the programmer. Some pilots prefer to manually lean with the knob once cruise power is set also.


Operation on either 100LL or Mogas is possible as no O2 sensor is required for operation. Automatic mixture control with altitude is standard as is the option to lean manually with the standard mixture knob. Many people prefer to manually lean via EGT once cruise altitude and power is set.

These systems are designed to use either the factory injectors or other standard top feed injectors. Details at: injectors.htm

We can supply systems for most 4, 6, and 8 cylinder automotive engine conversions. With SDS you have the option to manually lean or let the computer take care of things automatically. The EM-5 ECU has very low RF noise output and the elimination of carb heat makes operation simpler, safer, cheaper and lighter.


11/20/00 Knock Sensors on Aircraft

We don't recommend the use of knock sensors for engines powering aircraft. Generally speaking, air cooled engine have too much mechanical noise to be able to filter it out to hear the knocking. The second problem on opposed engines especially, is placement of the sensor. Most auto manufacturers spend countless hours determining optimum placement. You probably can't. The third concern is that the engine needs to actually knock before the ECU retards the timing which isn't good for it. Fourth, if you have the sensitivity set wrong, the ECU may retard the timing the full 25 degrees because of mechanical noise. You would lose over 25% power and this could cause an accident. Extremely high EGTs could also damage the engine. Finally, if you are running on 100LL and have reasonable manifold pressure limits, compression ratio and ignition timing, the engine WILL NOT knock in the first place.

Wiring and Modifying Systems

We get many aircraft owners who either want to do their own wiring harness or modify our systems in some way. Over 75% of the people who do these things have problems. Our advice is DON'T. Unless you do wiring for a living, this is simply a bad idea. People want to put cannon plugs at the firewall to make engine removal easier. Why? There are only about 5 connections to the engine and four are quick disconnects. How often are you pulling the engine? Even a total hab case can disconnect these plugs in 10 minutes. Every time you add another connection, you add another potential place for a fault to occur. If it ain't there, it can't fail. Some of the wiring that we have had returned to us is an absolute joke for an aircraft. Downright dangerous. If you modify the wiring or the system, don't bother calling us if your pride and joy ends up in the trees. Our system has proven to be extremely reliable if installed and operated as designed. Please use your noggin here.


Here is an example of some actual aircraft wiring returned to us. This is just waiting to break or short to ground. Proper strain relief and insulation is imperative for reliability.

We highly recommend that all EFI harness wires be run separately from other wires which carry high current/ voltage or any type of pulsing current signals. It has been shown that wires run parallel to each other in this fashion can lead to EMI and inductance coupling which may cause ECU running problems.


Reno Air Racing 2010

http://reports.airrace.org/2010/SuperSport.Gold.Results.Report.html

Questair Venture Continental 550 twin turbo fitted with SDS EM-4 6F. At Reno on Sept. 20/09 Mike Dacey finished third in Super Sport Class Gold at 382mph. Sept. 2010- Mike wins Super Sport Class at Reno. This is now the most powerful, direct drive Continental 550 in the world.

Mark Robinson photo

Mark Robinson photo

Mark Robinson photo

Thanks to Jan Peters at http://airrace.info/

http://www.youtube.com/watch?v=X6XcP0xJNIA
See Mike's Venture running at Reno 2008

Reno 2010 Super Sport videohttp://www.youtube.com/watch?v=LYCkgQXEwHU


Rotax 912 systems

We have been working with EFI on Rotax 912 engines since 2006 and the engines have been flying with SDS since 2007.

More photos and development details here: Click here

Thomas Hauklien from Edge Performance in Norway flies this turbocharged 912 powered Sonex with SDS.


Rotax 912 turbo with SDS on Sonex

Video of 912 EFI turbo engine running.


Performance is impressive


Hall sensor mounting detail


Thomas sent this photo recently of his turbo Sonex "I took a picture from the Sundays flight. 147KTS - 3000ft with only 30". Normally I cruise at 32-35" 5000rpm @ 8000-10.000ft with gives me 170KTS TAS. Not bad on a UL."


Rotax 912 EFI manifold from Edge Performance

Contact Thomas for any of your SDS needs in Europe and for Rotax 912 EFI kits:

http://www.edgeperformance.no/index.php

Email post@edgeperformance.no


2 Stroke R&D

We are currently testing EFI on this 2 cylinder, 2 stroke helicopter engine


Subaru Systems

We have supplied more systems for aviation Subarus than any other company and of course fly our own Subaru powered RV6A.

We are presently working on more aviation specific SDS products including parts to make replacement of the twin TEC units on NSI and Crossflow Subaru installations easier. A Hall effect sensor and mount is now available for Subaru EJ series engines. This will bolt into the existing OE magnetic sensor location, permitting magnet mounting on the crankcase side of the OE crank pulley. A new lightweight coil driver for EG33 OE COP ignitions and Suzuki G10 engines is also now available. We have an ECU internal driver system now available for STI and EZ30 COP ignition systems.


Subaru EJ/EG series Hall sensor and mount. Bolts onto stock magnetic sensor location. Applicable to EJ22 and EJ25, STI, EG33 engines $126US.


Hall mount installed on Subaru EG33 engine


For Subaru EA82 MPFI, EJ22, EJ25 and EG33 engines, we offer a version of our proven F system to control both fuel and ignition functions. These are calibrated in inches of mercury absolute and are suitable for both naturally aspirated and turbocharged engines. Please note, we cannot supply the OE style injector plugs if you are using the factory Subaru injectors on EJ and EG series engines.

We can now drive EJ255 (STI) and EZ30 coil on plug units directly out of the ECU if desired (below).


Standard 4F coil pack supplied to run most 4 cylinder engines. Two packs required for dual ignition.


Late model EJ25s using the coil pack above don't need our coil driver. This coil pack can be driven directly out of the SDS ECU. Be aware that this method gives you only a 5V tach signal option out of the ECU whereas the SDS coil pack also gives you 12 and 200V tach signal options.


The EG33 may use our supplied 6F coil pack or the OE coil on plug setup. The factory Subaru TPS can be used. Systems come with GM air and water temperature sensors or optional Bosch sensors. Our simple Hall effect crank sensor replaces the multiple factory magnetic crank and cam sensors.

Photos below of our twin turbo EG33 in our RV10



RV7 powered by Subaru EZ30 six cylinder owned by Bengt Bergsten in Sweden. EM-4 6F equipped.


Bjorn Anders Horne flies this EZ30 turbo powered RV7 in Norway. He reports 170 knots true on 9.25 Gal/hr. 230 hours on the setup as of Nov. 2012


Reg Clarke has flown this direct drive EJ25 powered Q2 for many years and 800 hours with SDS. 200 knots TAS at 12,500 feet on 5.5 gal/hr.


Allen Burruss from Stevensville, Montana flies this Glasair FT-S-II powered by an EZ36. 40 hours as of Nov. 2012. 180 mph on 6.5 gph.


Dennis Glaeser flies this RV7A powered by an EZ30 with IVO prop. 150 knots on 9.5 gph.


The photos below show the Crossflow EG33 powered Bushcaddy of the McWilliam brothers in Ontario, Canada. Now fitted with an SDS EM-4 6F and proper Garrett turbocharger. Now fitted with a Marcotte PSRU.


EJ25 turbo RV7 owned by Shane Getson, built by Ralph Inkster, Springbank Airport. EM-4 4F equipped.

http://s1105.photobucket.com/albums/h341/rv6ejguy/?action=view¤t=rv720110020.mp4
A short video of the engine running.

http://www.youtube.com/watch?v=q6bK8eTm4kc
Second flight video

http://www.youtube.com/watch?v=No7BnIDAp-Q
Some more video of high power engine runs, takeoff and overhead passes



Dan Shilling's Bearhawk, N61AK, with EG33, Autoflight gearbox, Ivo Prop, SDS EM-4 6F Located in Anchorage Alaska.



Gordon Wardstrom's Rover V8 powered Bearhawk. SDS equipped. Over 1000 trouble free hours to date. Runs head to head with IO-540 Bearhawks.


Suzuki/ Geo Applications

From Mike Crene of Kiwi Mustangs in New Zealand: Here are some photos of my Titan P-51 Mustang replica powered by the 2.5 liter Suzuki V-6 engine.

"I am flying the SDS EM4-6F in my Mustang with excellent results and reliability, and having the hand held programmer makes fine tuning ‘a breeze’. I am very pleased with the SDS system and would highly recommend it to anyone for cars, boats and aircraft."

SDS is the OE supplied EMS for Mini Merlin and Honda V6 powered Titan T51s.

The air to air photos below were taken by Kathy Bland.


Suzuki fitted with Autoflight gearbox and large prop


Ben Chester-Master in the UK flies this beautiful Titan T51 replica powered by a V6 Suzuki

http://www.moccasmustang.co.uk/

Ben is the UK distributor/ go to guy for the Titan T51 replicas.


Chris Gentry of T51 Aero in Florida, flies this 2.7L Suzuki powered Titan T51


Shaun Winson's R80 Tiger Moth replica in Australia. Suzuki G13B powered and SDS EM-4 4F equipped.



Aero Classics 111hp Suzuki 1300cc twin cam powered Tiger Moth replica in New Zealand. EM-4 4F equipped.


The photos below were sent along by Kasper Naef from Nelson BC. His turbo G13 powered highly modified Rans S-7 Courier (stretched fuselage and new wings) is running well with an SDS EM-4 4F system. Nice job Kasper.



Rick Robert's 1.3L Suzuki. EM-4 4F equipped.


Suzuki G10


Suzuki G10 system

For the basic system which includes ECU, wiring, coils, distributor blank off plate, Hall sensor and mount, Cam ring with magnets mounted, temp sensors, programmer, mixture knob and assorted fasteners, the price is $1700US. This will be available to all those who have their own port intake manifold solution. Not compatible with TBI manifolds. You'll require a MAP sensor to complete the kit $73 for atmo engines, $84 for turbo engines. This is a special order system, delivery time 3-4 weeks.

Michael Rutherford reports excellent performance from his turbo and SDS equipped G10 running through a Raven redrive.



Les Smoot's J-3 Kitten powered by 84 cubic inch 4A084 GPU engine fitted with EM-4 4D fuel injection system


Honda

Kasper Naef now has his Honda Fit engine flying with SDS fuel injection. He reports similar performance to the turbo 1300 Suzuki he replaced. About 5 gph at 5200 rpm and 100 mph on amphib floats.



Instrument Design Inc. (Tom Hodgson) is now test flying a Honda Fit engine fitted with an SDS EM-4 4F system after extensive ground testing. Flight time as of Dec. 10/09 is 33 hours.


We also supply Titan Aircraft with systems for the Honda V6 powered T51 replica fighters.

This is Jim Auman's beautiful Honda V6 powered T51 fitted with the 84 inch Whirlwind propeller.


04/20/04 Lycoming Applications

We have many people contacting us about using SDS on Lycoming engines. The main concerns with using EFI on these engines is shielding the injectors, wires and lines from heat radiating and conducting from the exhaust stacks. This is a major concern during idle and hot start conditions. The injectors should be mounted in the intake runners NOT the heads as the heads are way too hot. Our new billet injector bosses make this relatively easy. One or both mags can be eliminated by using the 4F system. The fuel system must have a provision to return fuel to the selected tank. Larger injectors are required than those on automotive applications due to the extremely large cylinders on these engines, despite the low specific hp output. An automotive type throttle body could be used to replace the carb. Tim Collard's O-320 powered Mustang 2 (below)has been flying with an SDS 4D for several years. Joe Block has been flying his SDS 4F equipped Lycoming Glastar (in links below) since June 2003. As of Jan. 2007, he had 470 hours on it. We are able to supply Siemens 72lb./hr. low impedance injectors for O-360/390 applications and 55 lb./hr. Siemens low impedance injectors for O-320s.

Peter Krok switched his 7A to Lycoming from Subaru and retained his SDS ECU with Robert Paisley's EFII system.


Tim Collard's O-320 powered Mustang 2. SDS 4D equipped



Injector installation details.


Note fire sleeve/ heat shielding to protect fuel line from infrared radiation due to proximity of exhaust pipes.

08/10/05 update from Tim Collard: "My Mustang 2 has been running on your system now for over 225 hours with no problems [other than my bad wiring]. Getting excellent fuel burns, very even temps, great start up and smooth running. Don't understand why everyone doesn't get a SDS system."



Joe Block's O-320-E2D powered Glastar is fitted with an SDS EM-4F

Joe has 470 hours on the installation so far and reports that he cruises at 30-50F lean of peak and 6.5 GPH at 75%. Operation is very smooth with very close EGTs between cylinders.



Photo showing typical components required to install SDS on a Lycoming engine. ECU, programmer, coil pack (2 required to fire all 8 plugs), dual fuel pumps, fuel pressure regulator, throttle body, injectors and bosses, Andair duplex fuel selector. Not shown is wiring harness, crank sensor and mixture knob. You need fuel return lines to the fuel tanks on aircraft having more than one tank.


Lycoming Bolt on Systems

Robert Paisley has been test flying an O-320 powered Taylorcraft with an SDS EM-4 4F, developing a full bolt on kit for the O-320/360 engines. Now available.

Info: www.flyefii.com

Protek offers a very nice fuel pump module: http://www.protekperformance.com/aircraft_parts/Fuel_System/Fuel_System.htm/


Continental Applications

Along with Mike Dacey's six cylinder Conti, we have done a number of smaller Conti engines. Mark Snow was an early SDS user on his C-85 powered Dragonfly, accumulating over 750 hours. Justin Mace currently has 350 hours on his SDS equipped, O-200 powered Dragonfly. See more details on these aircraft below:


Jabiru 2200/3300 Engines

We receive numerous requests about fitting EFI to the Jabiru 4 and 6 cylinder engines so have decided to produce some items to make installation easier like smaller, lightweight versions of our injector bosses to allow mounting of more compact injectors in the tight confines on these engines. We are currently working with clients on these installations and hope to be able to offer these parts and help on getting rid of those nasty carbs. We'd be interested in working with someone who could supply a 2200 or 3300 engine for mockup and design of additional EFI parts to possibly make a complete Jabiru engine kit available in the future.


Injector boss with 17lb. Bosch injector for Jabiru EFI installations


Injector installation on 3300 by Michael Crowder

Update Aug. 27/10

From John Milsteed in Australia who recently installed SDS on a 3300 engine: "The system is still working well, picked up around 8-10 kts indicated due to the rpm increase and fuel usage went from 26 Lts/hr. to around 18 Liters/hr.- not bad".

Some photos of John's installation below:

John is using the carb as a fuel backup and reports that works quite seamlessly.



Throttle body replaces Bing carb

Thomas Hauklien in Norway sent these photos of his customer's Jabiru 2200 powered Sonex fitted with SDS EFI. He reports 250 more rpm over the carb and the engine will idle down to 200 rpm!


VW Engines

Thomas Hauklien from Edge Performance in Norway sent us this photo of his turbocharged VW engined Sonex with SDS fitted:

See the engine running here: http://www.youtube.com/watch?v=SYEaTwKQcv0

Here is another nice video Thomas put together showing the whole installation: http://www.youtube.com/watch?v=UnkeUdwEF-w


Aircraft EFI Supplement click on this link: SDS aircraft EFI Supplement



New style injector bosses available with steel or aluminum bases. Threaded for 1/8 NPT fittings. Use standard Bosch type 14mm O-ring injectors. Makes fitting injection to Lycoming and Continental engines a lot easier. Revised nose contour makes them easier to weld to tubing.


Adjustable fuel pressure regulator with AN6 fittings. $220


Aircraft/ Engine Forums

http://groups.yahoo.com/group/FlySoob/

http://www.vansairforce.net/

http://groups.yahoo.com/group/titanmustang/


For a lead scavenger replacement for use in non certified applications from Decalin Chemicals.
Website: www.decalinchemicals.com
E-Mail:chris.lowery@sbcglobal.net
Phone 650-353-5062


Aircraft Related Tech Articles and Projects:

Racetech's RV6A Project
SDS EFI Supplement for Aircraft Applications
Suzuki G13 Hall Sensor/ Magnet Mounting Instructions
Auto Engines in Aircraft Part 2
Racetech's RV10 Project
Turbocharging Automotive Engines for Aircraft Applications
Subaru Powered Dragonflies
Suzuki Powered Snark
C-85 Powered Dragonfly
Metro/Tracker Powered Jenny and Spad Replicas
Thoughts on Redundancy
Auto vs. Certified
Turbos, Aircraft Engine HP and Fuel Burn Myths
EJ22 Engine
EJ22 Intake Manifold
EJ22 Alternator Mount
Marcotte Redrive
Vacuum Pump Mounting
Turbocharger Mounting
EJ22 Disassembly
Fixed Pitch vs. Adjustable Pitch Props
Cylinder Head Flow Benching
EJ22 Assembly
13B Powered Lancair 235
RV6A Photos
Direct Drive vs. Geared
Choosing an Aircraft Design
EFI Fuel Systems
Justin Mace's Continental Powered Dragonfly
Bill Baxter's EJ 22 Powered Glastar
EJ22 Powered Europa
John Petrie's EG33 Powered KIS Cruiser
EJ22 Turbo Discussion
Les Davenport's RV6A
Gordon Wardstrom's Rover Powered Bearhawk
Joe Block's Lycoming Powered Glastar
O2 Sensors and 100LL
Cooling the Subaru EJ22T
Subaru EG33 Intake Manifold
Subaru vs. Lycoming (the unabridged version of the April 2005 Kitplanes article.)
Deadstick Technique for RV Pilots
Backup Battery Considerations


SDS products are manufactured, supported and sold by:

Racetech Inc.
#5-304 Noorduyn Park
Calgary, Alberta, Canada
T3Z 3S8
Phone 403-671-4015, Fax 403-453-7687

E-mail:racetech1@telus.net


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