Just a word about MAP:  In a friend's Mooney with paper air filter element,
his MAP was 1" below local station pressure.  In a Cessna 182 with oiled
foam rubber filter, the difference was 2".  I never hear the rotary folks
talk about filters - I think most are using NO filter, so my comments above
are N/A.
   - But, if you use a filter - there is a difference in pressure drop thru
different type filters.  So, I would view a 2" drop as normal if using an
oiled foam filter.

Maybe we can normalize our reports as "MAP reading difference (below)
station pressure" (for Normally Aspirated).

Then in the air, we should all be hoping for "ram air effect" if we use
"racing type inlets really close to the prop", we would hope to see MAP
greater than atmospheric for the altitude we are running high speed at (like
50' off the runway at sunup with no wind for speed checks, etc)

David

----- Original Message ----- From: "Russell Duffy" <13brv3@bellsouth.net>
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
Sent: Sunday, September 05, 2004 9:25 PM
Subject: [FlyRotary] Rev 3.1 static tests


Greetings,

Well, my week of fiberglass hell seems to have paid off.  As you may recall,
I got 5500 rpm with my old inlet ducting, 5700 with the ducting removed,
5820 with the ducting removed, and short air horns on the TB.  Today, with
all the new inlet installed, I got 6000 static.  I'm pretty happy about
this.  Tracy reported 6200 at 120-130mph in climb, and I'm sure I can top
that now.

I only saw 27 MAP at full throttle static though, but I can't say I ever
tried this when I thought all was well (and was NA).  Has anyone tied their
plane down, and run full throttle to see what the MAP actually reads?  27
still sounds low, but I just don't think it can be improved in the current
configuration, and may just be a reporting error from the way the ports are
mounted in the TB.

The downside to all this success is cooling.  I used to be able to run on
the ground for minutes at full throttle without overheating.  Not anymore.
I exceed 200 in seconds at full throttle, and I saw a max of about 220
degrees for both water and oil during my brief-as-possible runs today.  The
water might be OK on climb with some airflow, but the oil is going to
overheat quickly.  It doesn't make sense to have more power, and not be able
to use it, so I'm sure my next big project is to improve the oil cooling.



Fortunately, after next weekend, I'll have a SlingShot to fly, while I
fiddle with the RV-3 for the rest of my life :-)



Cheers,

Rusty (one solution, leads to a new problem)