This system takes air from the engine cooling air box and directs it into the cockpit. The air at the air box nipple location is ambient temperature and is unrestricted ram air so there is a lot of it. The valve mounted on the firewall controls the air flow and also serves as a shut-off valve. The valve should be stainless steel for fire protection. For maximum efficiency, a 4” NACA Duct (scoop) can be installed backwards in the belly towards the tail to create a flow thru ventilation effect to handle the additional air.
This 4” NACA Duct can be installed in the belly of SX’s to improve the fresh air ventilation system.
Fresh air entering the cockpit has to get out somewhere. The duct shown is carbon fiber and they are available through many fiberglass parts suppliers. Doug keeps them in stock.