Technically, it should be installed with the angle to the rear to prevent pressurizing the carb with ram air. Doing so causes mixture problems as the diaphragm in the regulator in the carb is sensing static air, (hopefully), and the carb throat itself would be under a slight pressure. Not good.

Many people think you can get free supercharging through ram air entering a carb. Not really so. Studies have indicated that ram air only offers gains of 1 to 2 % at speeds of 150 mph, while causing carburetion difficulties. Race cars have hood scoops mostly to admit only cold, outside air to the carb(s), which does offer a useable benefit.

The stack is cut at an angle to prevent a venturi effect whereby the passing air would try to suck the air fuel mixture out of the carb in flight. Angle should go to the rear.

AV8TOR