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Rotax 912 fuel injection

Posted: Thu Apr 29, 2010 8:05 pm
by Mark Gregor
Can you add fuel injection to a rotax 912 on an LSA?

http://www.epapower.com/website/index.p ... iodivision

I think you would need manurfacturers OK first or?

Fuel injection sure would be nice.

Maybe rotax will update the 912 someday. I know they have the technology.

Jake

Posted: Fri Apr 30, 2010 10:25 am
by rsteele
For and S-LSA, the manufacturer would have to approve it. Which in my opinion would never happen as Rotax would no longer support the engine, AND they would have to sign off that the plane still meats all the LSA and ASTM standards.

For E-LSA, I doubt it, but that rule is even more confusing than the S-LSA rule, so maybe.

As an aside, this sort of mod' seems to go against everything that LSA is about. Get yourself an EAB and then you can do whatever you like. There is an outfit, in Colorado I think, that sell hopped up 914's that are reclaimed from Predator UAVs, as well as FI 912's, if I remember correctly. Not cheap though.

912 fuel injected

Posted: Fri Apr 30, 2010 4:05 pm
by roger lee
Hang tight for a year or so. Rotax is coming out with their own Mfg fuel injection. Can't tell you how I know, but they are. I bet it will add another $4K-$5k to a new engine.

Posted: Fri Apr 30, 2010 5:46 pm
by markfnkl
Hi Roger:

What would be the advantages of a fuel-injected Rotax?

Thanks,

Mark

Posted: Sat May 01, 2010 8:10 am
by FLA-CFI
markfnkl wrote:Hi Roger:

What would be the advantages of a fuel-injected Rotax?

Thanks,

Mark
Fuel distribution would be a little more even between cylinders for one....

Posted: Sat May 01, 2010 9:45 am
by dstclair
Potentially small gains in fuel efficiency (depending on the injection method) and weight (fuel injectors weigh less than carbs). Also,don't need to worry about carb ice :) There's also an argument for more responsive throttle but you won't see gain in top power (provided the carbs are appropriately configured). Of course, Rotax could elect to do a bit of reengineering to gain a few more HP in other ways to help market the update.

FI versus carbs borders on a religious debate although FI is most likely the base technology of the future. Might have more to do with manufacturing than a clear advantage. Marine is seeing increased FI engines so this might be a harbinger for us.

Posted: Sat May 01, 2010 2:28 pm
by Helen
The military does this on their Predator drones.

Helen

Posted: Sat May 01, 2010 10:42 pm
by Cub flyer
I'd like to try it.

The complexity of the constant depression bing carb plus using the choke.
instant start of the fuel injection would be ok. Reliability should be close or better.

What scares me is if there is dependance on electrical power and computers.
But the cars run on and on with fuel injection.

Some kind of mechanical fail safe limp home mode would be nice.

A diverter valve with a AeroVee carb instead of a carb heat valve? Alternate carb control?

Posted: Sun May 02, 2010 11:19 pm
by zaitcev
WWII fighters had fuel injection with mechanical computers (FW-190 in particular had a single-lever power control: no mixture adjustment or boost settings, like a jet). But yeah, I'm pretty sure Rotax is going to use a usual computer.

Posted: Mon May 03, 2010 7:16 am
by Cub flyer
Kitplanes had a pretty good article on the UL power engines.

They can limp home with sensors not working on the injection/fadec control.

Also optional dual computers, electrical bus.

Looks like a pretty neat engine.