912 EFI System

[Gravity_Knight]

The other advantages (usually) are, no choke, no carb heat (on this type of injection) and usually no mixture control. I'm kind of baffled with this one - as in their 7th picture down, they show and describe a "mixture knob". What for? On any efi system the primary advantage is the computer is supposed to be selecting mixture automatically - it's how the efficiency is usually gained. SO I don't know what the knob would be for or what the computer really does, if you still manually adjust mixture?

I come from the car world. I did an sdsefi system on a turbo 4Runner I built years back. They had this coarse mixture knob to allow you to make large swings to overall a/f ratios. It's really only mean't for initial tuning, once you have the system dialed in, it shouldn't be needed. I have tuned a lot of fuel injected stuff, both factory ecm's and stand-alones. The sds is not a bad system, but is clunky to work with and adjust in my opinion.

The benefits to FI in a plane would be, no carb heat to worry about, no mixture knob to worry about. Theoretical best a/f ratios regardless of temp, altitude etc. More accurate mixture equals more power/efficiency. Now I say theoretical because there is still room for error based on the tune and some other factors. But it's real close when done right.

And wether you have an efi system you can tweak (tuning wise) or a carb with a mixture knob, in my opinion they should have a wideband a/f gauge. This allows you to actually see in real time what a/f's your running at, and do something about it if it's off.

[Av8r3400]

Personally I like the idea of getting away from carb syncing...

[SkyPirate]

me too Larry and no ice although you should be able to sync carbs in your sleep now

[Esser]

I flew down to Calgary yesterday to see Ross who owns SDS with his partner. They have 1200 planes flying with their EFI products. The Rotax stuff is supposed to go through their Norwegian dealer.

I do think the controller is a little clunky but the system is beautiful. They have the 2-1 manifold set up and the 4-1 set up so you do have a couple of options.

The mixture knob is only there for set up or manual control if you so desire(sensor failure back up). You do not need to adjust it once you have your system dialled in. The ECU also has run away engine protection, knock sensing capabilities, and ignition advancing capabilities(Most Rotax operators wouldn't need this)

The system is bolt on and can be ready to fly in a weekend. It can take a couple of weeks to dial in your cod start(engine has to be cold)

On the Rotax they are seeing about 8-10hp gains or 8-10% fuel efficiency.

Long story short we will be going with the 4-1 manifold system on our 914. I'll keep you all posted

[Kurt.A]

Good Thread, I have done several automotive conversions and will be converting my 912 to EFI. The conversions I have done have been done using the Megasquirt system. All have performed flawlessly after set up. Those interested in doing this would be well advised to research the Megasquirt controller. They have incredible tune-ability as well as a broad range of add-on features.

Here is the FAQ page.
http://www.megamanual.com/MSFAQ.htm
Here is one of the better dealer pages
http://www.diyautotune.com/
And for those that just love to read here is the Forum
http://www.msextra.com/forums/index.php

The Megasquirt system is based on a DIY program but there is many resources available from suppliers and assemblers to tuners. They can be bought 1 resistor at a time to complete functioning systems with assembled wiring harnesses that are plug and play (automotive).

My intentions are to build 2 complete systems for redundancy. 2 in tank pumps, two controllers, dual o2 sensors, etc. Maybe overkill but extremely safe.