Paul, Welcome back!
While you were absent this came across one of the canard lists and just seemed more within your realm of knowledge and experience:

Ram air box truths (real PSI gain)
Gentlemen,
This issue has been explored and many of us have spent hundreds of dollars
or many hours to install a RAM air box in our aircraft to gain an expected
increase in performance. Truth be told, there isn't much gain under 200
mph. At least not enough to even register on the airspeed indicator.  I'll
explain why and you can decide for yourself.  This is probably why no one
will quote any increase in speed when you purchase a RAM airbox from them,
because there won't be any.
Here are the true hard facts using the following criteria:  (Publication:
Aerodynamics and Flight)
At   MSL Pressure 14.7 psi  (densest air possible on the planet)
At   200 MPH (if your plane will go this fast) direct air flow (non
obstructed, perfect flow)
At   59.02 degrees F  (15 degrees C)  Standard aeronautical calculation
temp at MSL

TOTAL INCREASE IN PRESSURE =  0.710 psi

By the way, any performance increase is assuming that there are zero bends,
curves, voids, filters elements or any other disturbance/blockage of the
flow into the cylinder head ports. And we all know that isn't the case in
our aircraft or engine induction design.  Now, go ahead and factor in
actual conditions and temp at 2000 to 8000 ft MSL along with your actual
airspeed (indicated pressure) and the fact that you are not getting
true/undisturbed RAM air into your PERFORMANCE DESIGNED Lycoming >>induction system.
You might see 1.5 HP at 2900 RPM's on an 0-320 engine running Wide
open Throttle.  Just don't pack a lunch before flight, you'll get the same
results.
Just passing along mathematical facts.

Paul, these guys quote line and verse from archives of stuff that has been tried on canards, more often than not finishing with the admonishment: "if Burt or Klaus is not doing it, don't bother"
I get the impression they just have not explored enough.
...just curious on your take, Chrissi

I agree with you. I have never seen Klaus take a pressure measurement
and his hangar is right across the taxi way from mine.
He does plenty of top speed measurements. But there are a zillion
variables doing it that way and it is very difficult to detect small improvements.
If one tends to see no improvement in the first try using a top speed test
they tend to conclude there is no advantage which could be a wrong conclusion.
A water manometer on the other hand can detect extremely low pressure changes
and consequently trends as well. 

Paul Lamar
 
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