Paul,
While I like the simplicity of the idea, and believe with the right
ramp profile it CAN work, dribble systems are never going to be as
efficient as FI. Fuel atomization is the first reason. By its very
nature this system can't be high pressure, it is a fixed pressure
variable orifice system. It would have to be over rich in most of the
mid range to be operable. Many things will run, most not very well. I
saw a photo of a guy that got himself out of the desert of Baha after
rolling his bug and smashing the carb. He ran the hose from the fuel
pump into the point end of a BIC pen he pulled the guts out of. Duct
tapped the thing over the inlet bell and it ran shoving gas out through
the little hole on the side of the pen! He even told the press guys that
it worked pretty well at "bout 50". Mechanical fuel pump made it a kind
of ultra-primitive FI. The flat slide idea could be ok but never as
precise as good FI. Perhaps as a redundant system would be its best use.

By the way I checked and Lectron is still in business. They have some
very sophisticated ground needle systems. They could be incorporated in
the center of the slide throttle to improve mixture control but then
your simplicity goes out the window. You're making a carb again. BTW the
system WOULD be subject to icing. Though typical carb heat could be used
with it.
Bill Jepson

It is not like this is a new idea. Klaus flies an Ellison
on his O-200 and gets 50 MPH at 200 MPH. What is inefficient
about that? Gravity feed no less. All the pumps do is fill
the header tank. I know half a dozen people running these
types of carbs and they are getting better MPG than we are
with EFI.

http://www.aeroconversions.com/carb_saying.html
http://www.ellison-fluid-systems.com/article/notaposa/notaposa.htm
http://revmasteraviation.com/products/revflow_injector_carburetor/index.htm

These are becoming universal on cert engines in experimental
airplanes because they are simple and relatively cheap.

If you have some data or documentation to support
your inefficient or atomization claims I liked to see it.

EFI is not worth the high cost and the redundant electrical
system required to make it safe.

Paul Lamar ...No rotor no motor.

Paul,

I think your original idea with the many small holes would work better
for atomization. That's the idea behind the Ellison fuel spray bar which
uses lots of tiny holes to achieve very fine atomization.

Regards,

Gordon.

Paul

Gordon has a good point.   A spray system, perhaps a double pipe (mini tank)
with a built in throttle valve that controls the flow to  holes drilled into
the P port Al. manifold pipe.  It would be placed just downstream of the
slide throttle. This eliminates slide throttle soak.  Fuel flow valves could
be linked to the throttle linkage  mechanically.  I think the design
parameters (read seal pressure friction) for handling flammable liquid and
air are not complimentary to put in the same valve mechanism. Said another
way the challenge would be to keep the slide press tightly against the fuel
inlet pipe while assuring fuel traveled laterally along the slide and out
the appropriate place while eliminating capillary action. Daunting but worth
thinking about. It is done in rotating cylinders within a pipe all the time
for fuel reserve and shut off valves though.


How about my linear gear on top of the slide idea I told you about several
weeks ago? Instead of a electric motor it could be a flow valve.  The same
rotating shaft that goes to the valve shaft goes to an arm.   Linkage to the
a lever makes the whole unit a lot more compact as well.

DougFir


Have you ever dropped a drop of water on a hot frying pan?
What happens to the water? It becomes water vapor
or steam doesn't it? We are going to use exhaust heat
to heat the slide throttle to 150 F or there abouts.

What is wrong with slide throttle soak?
The word soak implies that Teflon is a sponge.
Teflon is not a sponge.

What is wrong with a little capillary action?
The amount of fuel going into the slide throttle and thence
into the P-port is controlled by the leaning ball valve. I think
you are missing the significance of that point.
The metering part of the ramp is just a crude
approximation so the engine will run when started
and accelerate to take off speed. Anything between
8:1 to 18:1 air/fuel the engine will start and run. Fine
mixture control is done by the leaning valve. You set the
takeoff power by running the engine up to static RPM and
set the mixture for max RPM. It is a good habit to get
into anyway in case you find yourself at a high altitude
airport.

A grain of sand will defeat your rack and pinion.

Why make it complicated? Yes I know your Seawind engine is many
feet from the pilot but so is a 747 engine and Boeing
uses throttle control cables.

Paul Lamar ...No rotor no motor.

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