This is the configuration that Steve and Everett, (original Powersport) worked out that was very effective. (see photos attached) The photos show a 2 rotor mounted on an RV3, The engine mount wasn't the best they had ever used, but it shows their best cooling configuration. In the profile shot you see the stack of components. PSRU, 2 rotor, radiators/oil cooler. There are 3 equally sized heat exchangers. On this plane I believe they were all Setrab, but the manufacturer isn't that important. There are 2 water radiators arranged in a V with the oil cooler horizontal between the 2 water rads across the bottom separating the lower ends of the water coolers, thus \_/. They used various cowl inlets and didn't find a major difference there. There was an annular inlet on this set up. The inlet air flowed around the engine which allowed the engine air to be input and generally kept the accessories from overheating, At the rear of the engine there is a bulkhead fitted across the cowl and sealed. Opening for the engine air is directly behind the engine and permits the air to flow between the truncated v with the inside face of all 3 heat exchangers open. The flow is from the inside out toward the cowl and then exiting at the central lower location and out towards the rear in a conventional manner. Three equally sized rads is perfect for the rotary since the oil typically does about 30% of the heat transfer. The swirl pot and header tank are inside the "V" nearest the firewall. This layout was used on their primary RV4 test bed and worked great. A side-by-side like an RV6 would work even better with more room for exit air. The exhaust header is shrouded and has a blast tube in front to control exhaust heat. This layout should work with most of the engine mounts folks are using for the rotary. Sadly major rotary parts are getting difficult to find as this is a very airworthy layout.

Bill Jepson