[1965 Mustang]

Corvairs use manifold/engine cowling type heaters also. The one on my '63 Corvair puts out tons of heat but if there is the slightist oil leak into the cowling surrounding the engine the whole car gets stunk up when you use the heater. And mine stinks..... Corvair engines are completely encased with a cowling to regulate engine temperature. They have thermostats that open little doors at the back of the engine to regulate airflow. Probably most car guys know that already.