Decades before Manifold Destiny (the engine-block roadkill cookbook) Modern Mechanix published this guide to cooking with waste-heat from your car-exhaust while camping. Given that this was back in the era of leaded gasoline, I'm sure the car-exhaust imparted a magic flavor to the chow.
MEALS can literally be cooked on the run through the use of the automatic cooker shown in the photo above. The cooker is mounted on the rear bumper of the motor tourist’s car and an extension from the exhaust pipe connected up with it, as shown in the insert. The cooker contains a steam pressure kettle which is heated by the hot exhaust gases. An hour’s drive is quite sufficient to thoroughly cook meats and vegetables. Total weight of the unit is so slight that running qualities of the car remain quite unaffected. Motor tours are much more pleasant when one is assured of a well-prepared meal at the end of the trip.Link