Webra Thread .... clipped to accommodate list length

[george kennie]

Hey Jim,
It would take me 6 months to learn to do all that!

Jim_Woodward at beaerospace.com wrote:

>
> Hi Emory,
>
> Going to Apopka?  Good question.  Pump pressure and mixture go
> hand-n-hand.  If the engine is rich in the midrange on the ground, but
> exhibits symptoms such as:  popping sounds or puffs of smoke when
> adding power, moments of silence then catch at full rpm, or does not
> sustain power on uplines - you need more pump pressure, then readjust
> the carb for good ground running.  Reducing pump pressure may yield a
> good ground running, but it might not yield sustained power on
> uplines.  I run as much pump pressure as possible, while maintaining
> control over the fuel metering in the carburetor.  "Shamless plug" -
> thats the beauty of the MC carb.  You can run a lot of pump pressure,
> and just bias the control arm adjustment a little on the on the carb,
> then use your transmitter to tune the rest of the throttle-mixture
> curve.  This way, you always have enough pump pressure.  The real test
> of the MC carb is in-flight performance.  If there are any dead spots,
> just note about where the throttle stick was, go into the program, and
> richen or lean in just that area.  For instance, you can leave the
> idle fairly rich, so the engine slows down right away when you reduce
> throttle to idle, but if you lean a couple points just above it you
> get instant "zippy" throttle response, then make the top point a
> little rich to control the top rpm figure.  Once you get the right
> mixture everywhere you want it, use the transmitters actual
> "throttle-curve" to set the amount of power you want for a given stick
> position.  Use this feature get the right velocity for the throttle
> stick position you usually fly.  I think I fly mostly around the
> 5/8-3/4" throttle stick position.  My throtte curve is steep at first
> to give some prop blast over the rudder for stall turns, then flattens
> out quite a bit - barely rising.  The last two & three points of the
> curve rise very steeply - like a very smooooooooth switch!  Thus, I
> get 'full' power only at the last two & three positions of stick
> movement.  The best part is that as soon as you get back off those top
> 2 or 3 throttle stick points, the engines rpm has really dropped -
> instant speed mangement while keeping the throttle stick in the
> position I like to maneuver in!  Finaly, mix the throttle curve to a
> knob near the throttle stick, you can adjust the rpm while in flight
> (although the knob affects the entire curve).  There is a learning
> curve, but the overall action is superior.
> Jim w.
>
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