sorry Ulysses, Ive confused you and myself as well... lol
like I said, their true purpose is to remove air from a particular area such as the engine compartment. If mounted in certain positions (like I also said, there are literally thousands of variables to consider) then NACA ducts CAN be used as an inlet to provide air and positive pressure, BUT their original and most beneficial purpose is to create a vacuum to remove air... its so difficult to explain things like that with a keyboard... it would be much easier to get my point across in person.
Joe: in EdmontonGTS's defense, I honestly feel that DC's purpose for adding the NACA duct was to provide an outlet for the stream of air coming up from behind the bumper cover... Ill try to explain without confusing everyone... you see, when at speed, there is a large amount of cool, fresh air coming up from the bottom of the Vipers, the NACA duct provides an outlet for whatever air isnt pulled into the air box - since the 'outlet' is smaller than the 'inlet', you have pressure building up - but since the engine (in theory) uses more air at higher speeds/rpms, the pressure inside the engine compartment should remain somewhat stable. The vacuum created by the NACA duct helps to 'pull' fresh air into the engine compartment, creating more horsepower... make sense??
based on this, I feel that the Vipair would be more effective and add more power as compared to the Vararam... IMHO - same theory for open filters too
*I dont know how many GenII owners drive in the rain, but assuming you dont stop the vehicle for a long period of time, you will notice that not a drop of rain enters the engine compartment... why?? You've got a huge hole in the middle of your hood and not one single drop of rain enters... reason being is that this 'stream of air' that EdmontonGTS was referring to earlier 'pulls' rain and moisture across the NACA duct, preventing any rain from entering your engine compartment...
EdmontonGTS: mail sent
9 seconds: like I said earlier, there are thousands of variables to consider in placement of a NACA duct... if you look closely at placement and position of the window-mounted NACA duct that NASCAR drivers use, you should see how it provides positive air pressure