[kach22i]

Good point.

Opinions? Duck tail vs. Carrera Tail (aerodynamically speaking) - Rennlist Discussion Forums


When Porsche first put the "ducktail" on the 911 it decreased lift and increased cooling by building up air pressure before the tail and allowing the fan to draw in more air.

http://forums.pelicanparts.com/porsc...to-engine.html


From the above thread:

Originally Posted by Walter_Middie

I'm an aerodynamic engineer and I usually stay out of these discussions because they deteriorate quickly. I'll just say no - cutting slots in the spoiler will not help.

The spoiler works completely differently than a wing. The spoiler spoils and separates the airflow coming off the roof, creating a high pressure area on the back window and top of engine lid where the engine airflow intake is (as shown in your picture). Engine cooling air is increased because the intake is now in a high pressure region, and air is forced into the engine compartment. Cutting the hole shown in blue will decrease the effectiveness of the spoiler and decrease the amount of pressure pushing air into the engine compartment.