After a year and a half of deployment and assorted upgrades, my RV-6
   finally got back in the skys.  And she did great.

   The most significant upgrade was the new cowl and new larger radiator.
   (see picture).  Some of you may have participated in the 'smiley' cowl
   vs. 'OH' cowl debate.  Smiley cowl won on the basis of aesthetics, but
   there was a concern that that boundary layer issues (and the fact that
   the intake is several inches back from the prop) would prevent adequate
   cooling.  The other concern of mine was exit air balance between coolant
   and oil.  Both issues seemed to not be a significant factor.  Oil and
   water temps now were essentially the same, with the oil just slightly
   warmer.  Temps for both peaked at about 150, despite the mid 80's
   ambient temp and a warm-soaked engine (I am living at a tie-down now
   adays).  I limited my MAP to 30" and was at 26" for most of the flight
   (at 6500'), but those temps should allow continuous power well into the
   mid 30's for MAP.

   I made what I thought was a light weight and well designed cowl flap
   integrated into the radiator mount (see open/closed pictures), but as
   was my prior experience, the cowl flap did not have much authority to
   affect the cooling system.  The only difference today was that my temps
   are borderline too cold, instead of borderline too hot.

   I am expecting some increased cooling drag from the BAI (big ass
   intake), but at least it was not remarkable enough to notice on this
   flight.  More accurate data to follow.

   Other upgrades included new nav antenna, marker antenna, subdued
   satellite antennas, muffler, new interior, and about 50 smaller items
   and I was pleased with all.  In fact, my biggest issue with todays
   flight was that Sirius radio does not come in very well while upside
   down and the MP3 player is the best option for  aerobatics. Maybe I
   should have gotten XM, but the Sirius radios all come detachable so
   that
   I can easily use the same radio in my car and plane.

   Any day you fly instead of build is a great day  :-)

   --
   David Leonard

   Turbo Rotary RV-6 N4VY
   http://N4VY.RotaryRoster.net <http://N4VY.RotaryRoster.net>
   http://RotaryRoster.net

   Nice job on the scoop and cowl flap Dave.
   The cowl flap needs some end plates.

   Got any pictures of the inside of the cowl?

   Seven Stock is  September 22nd this year. Since I am half way down
   to your
   house can I come on down and take some pictures of the inside of the
   cowl?

   What is the rad core dimensions now and what was it in the days of old.
   No pictures of the rad were included.

   Paul Lamar ...No rotor no motor.

   Love the new scoop... airplane looks like it is smiling!
   Larry

   One would think almost 50% more core volume would have made a larger
   difference. This confirms the old rule of thumb on heat exchangers.
   The the first half does 75% of the cooling.

   --
   Paul Lamar ...No rotor no motor.


Yup, that's the rub.