Anderson Ed wrote:

Some good suggestion, Paul

        I presume my two feet of five inch dia hose does not qualify as a
diffuser {{:>}.  The new plenum is 8" deep from opening that the 5" hose
sticks in to the oil cooler (got some new photos will send to Don Mack
to put on his web site to show new plenum).  Going to be tough to move
the oil cooler forward as then it will end up just behind the right
radiator with me back to having to make a 90 turn with the hose, been
there done that.  Since oil temp is now staying below 210F except for
extend periods at 6000 rpm, I sort of feel I have a solution that just
needs some refinement perhaps like a better shaped cowl opening as I
simply cut a  NACA-like hole in the fiberglass.  It still has the sharp
edges, so I might try to see if rounding the edges of the hole perhaps
just putting one some split plastic small dia hose could give me that
little improvement I still need.

OK Ed. Moving it forward is out of the question. 

I would not round those edges. NACA ducts work by curling the air layer
near the surface into two small vortexes that enter the hole. Several
tricks
have been used to enhance their performance. One is to install a ridge
along
the edge. Just the opposite of rounding the edges. Another trick and
this
has come up only recently and that is to install vortex generators in
front of the NACA duct. Don't ask me where as I don't have the answer 
right at the moment. PL

Thats the thing about experimenting, you get to do it better the second,
third, etc., time around.

I agreed tedious and careful pressure measurements are needed, its just
that between trying to get started on a new intake manifold and other
things - those that can get by without immediate attention are not
getting done at this time.  And then I seem to keep coming up with a
gremlin here (rough running) and a gremlin there ( had to fix fuel leak
from right left fuel tank), finally got overhead dome light working
(Short in dimmer circuit), fixed a voltage reading that varied from zero
to 14 volts (loose terminal on lead to voltmeter), etc. Hey, but whos
complaining if all were working perfectedly then I would have to take up
golf to occupy all that time {:>}.

Again, Paul, I do appreciate all suggestions and I recognize their
value, just the time factor at this time precludes me from getting it
all done.  I also want to run a compression check this weekend to see if
that may be contributing to my lesser than expected HP as well as seeing
if fouling plugs contributes to the rought running.

Ed

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