Is that a stock Mazda 2nd gen intercooler we are looking at there Dave?
Looks like you have room to build a wedge diffuser for the top of the
rad fed by a scoop under the prop. That should solve the water
temp problem.

Paul Lamar

Right you are, Paul.  Stock 2nd gen.  You are sort of right about the
defuser. it is tight but could be made to fit.  But it would be a waste to
cover the entire rad.  All that air coming out of the oil cooler and
intercooler is already slowed down and not too warm.  After all, it is
cooling OK for flight now.

I also feel that the oil and inter cooler are probably not able to handle
all the pressure in the diffusers and pressure is probably spilling out the
front (if that makes sense).

My solution (after I fly off my 40 hrs) is to build a diffuser over the last
1/4 of the rad, and feed it with cool air bled from the difussers(like a 2"
scat tube from each). This will allow most of the original cooling air to go
through the first 3/4 of the rad, then add a finish of cool air right before
returning to the engine.

Add some improved insulation around the turbo and plug the few remaining
holes in the cowl and I should be pretty close.

Adding an additional inlet would be the next step if that doesn't work (got
to keep down that cooling drag).

I am skeptical about your idea of removing the cowl flap(& the rad cover).
(But I will probably try it some day 'cause it probably won't make me fall
out of the sky.)  High pressure area? No doubt about it.  40% of forward
speed, I doubt it in this case.  It seems to me it should be proportional to
the change in surface area, less the resistance encountered.

I cant remember the exact numbers, but each inlet is about 3.5 x 9 in.=
about 60 sqr in. of inlet.  rad area is roughly 25x28 or 675 sqr in.  So
assuming all the air coming in the inlet goes through the rad, it would
still only be about a 10th the forward speed.  Subtract from that the losses
due to leakage and resistance, add some velocity for heating, and we are
still at less than 10% forward speed.  My guess is that I would cool
significantly worse with the cowl flap off (obviously I felt that way or I
never would have done all that glass work I hate so much) - but it never
hurts to try.

David Leonard
The Rotary Roster
http://members.aol.com\_ht_a\rotaryroster\index.html

Well Dave a $10 water manometer will take out all the guess work.

Paul lamar

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