Randy here is that stuff on the Ellison carb.

   Paul Lamar



The hole pattern on the fluid shaft does not appear to be linear. How
did they come up with the layout of the holes?, Do rotaries have a
linear demand for fuel as RPMs increase?, (4 stroke piston engines are
not linear)
Why not use larger holes as the throttle slide opening gets larger? It
would be easy to fine tune the mix electronically using the
leaning/enrichment lever, and still have a base mixture available if the
electric control devise fails.

Ed Carver

Probably by experiment. There are all sorts of things going
on inside a carb throat aerodynamically speaking. Lots of
turbulence. Change the hole pattern at your own peril :)

Ellison seems obsessed with atomization. How much of that
is science and how much is marketing remains to be seen.
He makes a big deal about it in his adverts.

I am not really sure how that effects BSFC because so far I cannot
find any hard data on the subject. Most of the R&D on it
appears to be done on diesel fuel.

http://tinyurl.com/23phdey

"Three injectors with different nozzle geometries were tested in a multicylinder diesel engine with a high-pressure common-rail injection system. Various injection pressures were tested along with exhaust gas recirculation to achieve low NOx and soot emissions. The injectors used in the study included a six-hole nozzle, a ten-hole nozzle, and a six-hole convergent nozzle with a K-factor of 3. All three injectors had the same flow numbers. All three injectors tested were effective in reducing NOx and soot emissions at appropriate conditions."

I do know the longer the runner length between when the fuel is
introduced into the air stream the longer gasoline has a chance to
evaporate. That is one thing Ellison has no control over. On a flat
engine with one carb the runner length varies. On a Rotec radial
they are all roughly the same length.

In our p-port case if one used two Ellisons one would place them
close to the rotor housings for idle reasons. In the side port
case this is less important and one could use one larger Ellison at
the beginning of the manifold.

The big advantage of an aircraft carb is the engine will keep
running if you have mags with no generator-battery electricity.
(As Doug will tell you I hate electric cars :)) I just bought an
old fashion Maglite with 5 dry cell D batteries because my
A&P wife had only rechargeable flash lights lying around the house.
Every time you really needed them the battery was dead :)

The Maglite works for years and gives you plenty of warning.

Paul Lamar