Charlie: Yeah my drawing isn't too good -- done free-hand with a mouse in "paint" ...
Kelly: That is a great looking rad and hose options kit from Rywire ...
Steve: I remember your write-up on the Vee belly radiator and scoop but not sure if your air is entering at the wide end of Vee (I think yes because of hose connectors visible) ... I'm thinking of similar except under the cowling.  I don't have a metal under-belly for attachment nor the airspeed of your RV, so with the same setup your machine would have 1.5 - 1.7 times the cooling capacity.  Like WWII fighters with V12 liquid-cooled engines, it appears that efficient cooling relies on airspeed as much as anything else.
Jeff

Mine's on the side. When I flipped the angle, I was able to move the rad aft quite a bit, which gave me more room to tilt out (down, for you?) at the front. Regardless of tilt,  your bottom drawing's dashed line is much closer to what worked for me. Except mines a relatively smooth curve all the way to the inlet. It's worth playing with the cardboard & tape to find the most effective curve. My 1st effort, which was after Tracy's advice, still had nowhere near enough pinch at the aft end. I had to fill back there with spray foam and re-contour quite a bit. Once I got even flow across the core, I glassed over the new foam.

I hate to keep saying this, but mine hasn't flown. I know the air flow is even across the face of the core, but I really don't know how *much* air is flowing. But it is scaled fairly closely to what Tracy did in the RV-8/20B install, so I'm hopeful.

Charlie

-----Original Message-----
From: Jeff Whaley
Sent: July-31-18 12:04 PM
To: 'Rotary motors in aircraft'
Subject: RE: Using Fluidyne oil coolers as Primary Radiator

Yes, I did consider tilting the front end down Vs up but what I remember is there becomes an interference with the 90 degree 1.5 inch hose connections into the radiator as they get up against the engine and mount ... it looks better from the "French curve" diffuser aspect ... the drawing isn't to scale either so there is also a limit to the down-tilt before the cowling gets really ugly.
Jeff