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SDS EM5 installed weight

vlittle

Well Known Member
Question for Ross:

Comparing apples:
What is the total installed weight of your EM5 dual injection/ignition system (4 cylinder)? This should include everything except the electrons.

How does this weight compare to the equivalent dual mag/carb'd equivalent or the dual mag/FI System?

Thanks
 
I don't know the weight of of the legacy bits but here are the typical weights of our stuff:

Single ECU 4 cyl.: 15.5 lbs.
Dual ECU 4 cyl.: 17 lbs.
Single ECU 6 cyl.: 18 lbs.
Dual ECU 6 cyl.: 20 lbs.

All systems here would have 2 coil packs and the dual fuel pump module.

Updraft 6 cylinder systems are slightly lighter than horizontal induction systems.

These weights don't include plug wires.
 
Vern,
I intend to do a weight comparison at the aircraft level after my installation and expect a net reduction, but as I’m doing some significant remodeling it will be very hard to do an apples to apples.
That said, I’ve documented the rebuild process here, and I might be able to shed some helpful insight below.

Without weighing each related component, I’d say there is a weight advantage to the SDS fuel pump configuration, a significant weight advantage to the SDS throttle body vs. servo or carb, and a significant advantage to the SDS coil/hall sensor compared to the magnetos. On the other hand, the weight edge goes to the legacy parts when comparing the injector bodies and lines.

2h72osx.jpg


Then there is the ECU to deal with. It’s not required in either fuel or ignition system for legacy, so it’s really just added weight in a comparison scenario. Of course there is the extra fuel lines for the return system too. If I had to guess, after handling all these parts, I’d have to say the installed system is pretty close to a wash, with maybe a slight edge to the SDS (if comparing a Bendix style FI)

2q3c8di.jpg


Of course, the backup power scheme is a huge variable – ranging from no requirement (for a Reno race only aircraft), to an elaborate IFR, ocean crossing scheme. I’m adding a second battery to my airplane and I still think I’m going to come out lighter than it was (again, due to a bunch of other work).
 
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AFP lists their FM-200A kit at $3187.50
Spruce is selling Bendix mags for around $2K ea, no harness or plugs, so at least $7K total for fuel and spark all new. Slicks maybe a bit cheaper than that.
AERO is selling overhauled ones for around $1K ea.

Complete SDS kit with dual ECUs and all options (includes dual pumps, plugs and wires) is currently $6209US.
 
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Magneto weight

Looks like the Bendix 6 cyl units on the 550-G/N weight 5 3/4 lb ea. Dang - I did not know those parts were that heavy. $676 ea at Aero in Stock..

Wires will run ya $620 for the set, and those weigh 5lbs.

Plugs are $26 ea, at .3 lb ea for a total of 3.6lb

This parts list will also run ya almost $2300, but add shipping and I'd guess it will got to $2400 easily.

All that totals up to 20.1lb, or about the same as the entire SDS setup less wires & plugs. I'll get weights on the pumps (I'm sticking with the engine driven pump + a boost pump) as soon as I get the pump on hand.

Keep in mind this is a TCM550-G/N setup.

Best,
Mark
 
It looks to be a lot easier to install from new rather than convert an existing install. Michael is rebuildinghis entire FWF plus more.... but having fun!

The weight of a dual battery/alternator to feed electrons is mitigated by the general needs of all electric panels these days, so it's not just for the engine. If I have the kahunas to use Earth-X batteries, so much the better.

I think the best way to compare all-up costs would be to get quotes from engine builders such as Aero Sport. My guess is that a full-up dual SDS System would be similar cost to a conventional fuel-injected, dual EI system with electric pump.

The SDS system would require the extra duplex valve and return line compared to a Bendix FI.

On another note: in my experience, the engine builders have some difficulty with new fangled stuff. I had to redo some wiring terminals on my Electroair system that was installed on my 540 (poorly crimped terminals), and the crank timing wheel had been improperly installed, leading to a sudden in-flight failure (!).

My advice to Ross is to make the systems as turnkey and foolproof as possible, because if someone can screw it up, someone will!

Some folks, like Michael, truly enjoy the process, and in retrospect, I should have installed the Electroair system myself because I trust my handiwork more than a wrench-turner dealing with electronics (apologies to wrench-turners).

I'm looking at SDS, because other than being fine Canadian kids, I anticipate that the new Avgas will be oxygen sensor friendly, leading to much more sophisticated engine control and economy.

Thanks for the great info.
 
EFI is relatively new to most of the engine builders. They are, as you observed, more comfortable with old school carbs, mags and Bendix FI. At the same time, they realize that more customers are asking for EFI for their engine builds and they are going to have to learn about it if they want to build those engines.

I've made several trips out to Aerosport to help hook up and run engines there and train some of their guys on SDS. I'll probably be out again later this year. The younger guys are keener to learn and perhaps more comfortable with computers and electronics as that's all they've grown up with. Aerosport has test harnesses to run 4 and 6 cylinder Lycomings so the airframe wiring is not butchered up test running.

Barrett has also installed a couple SDS EM-5s on 540s. Lycon has had discussions with us too.

The installation is pretty foolproof now outside of the FF wiring tailoring and crimping which is hard for us to build entirely due to different routing and airframes. We do custom make each harness for each client to their length and termination specs however.

We're trying to include every part needed and improve the documentation continually based on customer feedback. I'm also starting to shoot more video tutorials on various aspects of the installation and use of SDS products.

We're designing new CNC'd parts all the time to be able to fit more engine/ airframe combos too and make installation easier.
 
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Vern
Hop in one of your wonder machines & point it East for 90 minutes or so. Ross & or I can show you how complicated (or not) to install the system. We might even buy you lunch!
 
It looks to be a lot easier to install from new rather than convert an existing install. Michael is rebuildinghis entire FWF plus more.... but having fun!

The weight of a dual battery/alternator to feed electrons is mitigated by the general needs of all electric panels these days, so it's not just for the engine. If I have the kahunas to use Earth-X batteries, so much the better.

I think the best way to compare all-up costs would be to get quotes from engine builders such as Aero Sport. My guess is that a full-up dual SDS System would be similar cost to a conventional fuel-injected, dual EI system with electric pump.

The SDS system would require the extra duplex valve and return line compared to a Bendix FI.

On another note: in my experience, the engine builders have some difficulty with new fangled stuff. I had to redo some wiring terminals on my Electroair system that was installed on my 540 (poorly crimped terminals), and the crank timing wheel had been improperly installed, leading to a sudden in-flight failure (!).

My advice to Ross is to make the systems as turnkey and foolproof as possible, because if someone can screw it up, someone will!

Some folks, like Michael, truly enjoy the process, and in retrospect, I should have installed the Electroair system myself because I trust my handiwork more than a wrench-turner dealing with electronics (apologies to wrench-turners).

I'm looking at SDS, because other than being fine Canadian kids, I anticipate that the new Avgas will be oxygen sensor friendly, leading to much more sophisticated engine control and economy.

Thanks for the great info.
 
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