EFI Jabiru 3300

[hfrensch]

I would like to give a brief description of the Electronic fuel injection I run on my 6cyl jab. The sytem is the simplest I could come up with after many years of trial and error. In my previous job (retired July 2003) I worked for Mitsubishi Motors Australia in product development . I managed the engine development and testing department. This gave me the the ability to source parts and develop the EFI system I am currently using.

 

I have run this EFI on my Jab for 16month, it has done 130 trouble free hours on the engine. Fuel burn is between 14 to 17 ltrs/hr with good power output. Longest trip was from Wellington South Aust to Narramine last Easter.

 

This system uses throttle body injection. The throttle body is fitted with 2x32mm blades . The injectors are on the engine side of the blades. For engine load a MAP(manifold absolute pressure) sensor is used. This is the simplest and most accurate way to take care of engine load and altitude correction. Air inlet temp sensor is used to help with air density correction and is fitted at the inlet to the throttle body. A hall effect pick up is used to monitor engine RPM. I decided not to use a engine temp sensor because it is difficult on a air cooled engine to get the type of curve I wanted. In its place I use a 0-10K ohm pot (rehostat) which is used like a choke on a carb engine and is only required for start on a cold day.No TPS ( throttle position sensor) is used and this helped to simplify the system. The ECU (electronic control unit) which runs the system is a Haltec F9 fuel only unit. The fuel supply is taken care of by a high pressure electric pump and the pressure is regulated by a regulator referenced to manifold pressure.

 

As you can see its a very basic system but to get it to work correctly the fuel maps had to be set up accurately. This was and is a very difficult job and engine failure can be the result of wrong mapping. Once the maps are set up for al load and RPM condition the air fuel ratio will not vary regardless of conditions because the ECU corrects for the load,temp and atmospherc changes. All I know is my Jab is a pleasure to fly climbs at 2000ft/min cruises at 115Knts indicated at 2600rpm. VNE(132knts) can be achieved on climb.

 

 

[Galpin]

Are able and willing to post a drawing (photos perhaps) of your EFI setup on the 3300?

 

I have been looking for this kind of setup for some time.

 

Thanks

 

 

[hfrensch]

I will post some photos when I work out how to do it.

 

 

[BigPete]

With your expertise and background on fuel injection (not to mention all your hard work) I think Jabiru should employ you to do the 2200.

 

My 2 cents worth...

 

regards

 

 

[Guest AusDarren]

Thanks for the run down.

 

your in a fairly unique position to have the level of know how to do that successfully. Has Rod Stiff Seen your implementation?

 

The business of R&D is one I try to avoid. Even simple mods can have unintended consequences, and often there are trade offs to balance.

 

Am I likely to get a better result than the factory team? Probably not..

 

though you are in a much better position with your Experience at Mitsubishi, than most of us..

 

(by the way I REALLY love my Magna! 3.5 injected Oct 02 LE)

 

Many thanks,

 

AusDarren

 

 

[jwatts]

Good work and well done hfrensch. No doubt you have put a lot of effort into this project but are now being rewarded. I am shortly ordering my J430 kit and once completed will want to do alteration too.

 

Keep up your great work!

 

Jayden

 

 

[eightyknots]

EFI and ICING

 

As you can see its a very basic system but to get it to work correctly the fuel maps had to be set up accurately. This was and is a very difficult job and engine failure can be the result of wrong mapping. Once the maps are set up for al load and RPM condition the air fuel ratio will not vary regardless of conditions because the ECU corrects for the load,temp and atmospherc changes. All I know is my Jab is a pleasure to fly climbs at 2000ft/min cruises at 115Knts indicated at 2600rpm. VNE(132knts) can be achieved on climb.

Hi hfrensch,

 

I was wondering if your system overcomes icing problems as well? (of course it can't be carb icing because there isn't one!).

 

Also, have you approached the Jab people to see if they could use the system? My feeling is that EFI would enhance the product and they may be pretty willing to talk to you.

 

 

[jetjr]

Jabiru wont even entertain it

 

ALL products they sell must be "certified" Much of thier sales is LSA Aircraft now.

 

Until someone come sup with a certified ECU, Jab wont touch it

 

In saying that EFI is very attractive for Home and Factory assist builts and I hope someone gets an EFI kit sorted out

 

 

[bushpilot]

Amazing HF.. Do you have any idea what hp it is making? And how is the consumption - at say 115kts cruise?

 

 

[jetjr]

Be aware this topic is 3 years old

 

There is a company selling parts to inject Jab engines

 

Simple Digital Systems

 

Amazing results

 

~ $2K plus fitting which is a bit complex apparantly

 

 

[jetjr]

These new kits vary a fair bit from Helmuts work I think.

 

He did great work but had to start from scratch and "wrote" his own program using std automotive ECU.

 

These new ones are preprogrammed and simply need adjustment. They are also purpose built for aircraft

 

Also they use port injection - 6 injectors, not 2 like Helmut so enables you to overcome intake differences too which is what causes uneven EGT etc with carb.

 

 

[jwatts]

med and simply need adjustment. They are also purpose built for aircraftAlso they use port injection - 6 injectors, not 2 like Helmut so enables you to overcome intake differences too which is what causes uneven EGT etc with carb.

I had a look on their website, sounds like a good system but however, you need to be able to weld in the holders for injectors on the inlet manifold...etc etc. There would be A LOT of time to convert the system over (and it wouldn't be for the faint hearted!). Mind you, there would be many benefits.

 

Jayden