The following is straight from the BME Manual.

ENGINE PLACEMENT:

If at all possible, mount the engine so that it is completely enclosed within the cowl, especially the carburetor. This will allow the engine to run at its best. If the engine is mounted such that the carburetor is sticking out of the cowl, it is altogether possible that the carb will be subjected to irregular airflow and as a result, may run erratically.

I am confused. Some say I should cut the bottom half off of the cowling to open it up so I have at least twice as much air flowing out than in.

The manual is suggesting to completely enclose the engine in the cowling.

Hlep!!! Any comments would be helpfull.

I have attached a picture of the cowling.