Thanks, Greg.  You bring up good points for discussion.

Greg Bullough wrote:
> 
> At 06:34 PM 9/21/99 -0500, you wrote:
> >I expect 5.4 gph for a moderate altitude cruise.  I get much lower fuel
> >consumptions (4.5-5.0 or lower are possible if I go high in spite of
the
> >climb, because I lean accurately.
> 
> A lot of us don't have a mixture control!

I urge you to get yours reconnected.  The mixture control in the
Stromberg carb works just fine if you clean out the carb air passages
and that little plate with the variable sized holes. [You really NEED to
make sure those passages and holes are clean even if you're wired full
rich or you could get unexpected leaning from a clog-up.]

 
> >If you pump energy into the plane going up, you can get it back during
> >the descent.  Rather than diving down at high speed, keep your speed
> >down and reduce power 30-40 miles out.  A 300-400 fpm descent at about
> >85 mph indicated will recover the majority of the energy you invested
in
> >the climb.
> 
> Don't forget that carb heat when you back off the power. On the route
home
> from Columbus to NJ, as soon as I dropped back to 2100 RPM, I started
> showing signs of ice. (No visible moisture at altitude, some down in the
> valleys and about 60 degrees OAT.)

I tend to stay in the green arc.  Then I pull carb heat for half minute
or a minute every 5-10 minutes. I would NOT suggest extended glides at
very low power settings.  But, at 2200 rpm at 85-90 mph, the engine is
generating heat and, with the clearing carb heat intervals, I would not
expect any problems.

> >This can pay off.  I've flown from Iowa to Chester Connecticut with
only
> >two fuel stops and Peoria to Sun-n-fun with only two fuel stops.
> 
> It can pay off if the engine packs it in, also. Lots more choices. But
which
> carb are you running?

I've got the Stromberg carb.  The one that the people who haven't ever
tried it PROPERLY think doesn't let you lean properly.  Actually, it
does let me lean quite well.  I got a low-cost ($99) egt from K&S that
has the large temperature increments.  With this indicator, I can choose
a 10 degree increment of temperature.  I lean to peak and a little past
to be sure of where the peak is.  Then I push in to 50 degrees down on
the rich side for cruise and 100 degrees rich for max power as
recommended in the books.  After settling on the desired temp, I turn
the adjustment knob so the needle is on a special wide mark that makes
deviations very easy to see. It works well.  It's not instant. I make an
adjustment and wait a moment to see the result.

Be aware that I find that I can't lean with ANY accuracy by sound in my
plane.

The value?  On a cruise, I can get 26 or so mpg under the right
circumstances.

-- 
Ed Burkhead
Peoria, Ill.
N3802H

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