
First off: This is no way an attack on the picture or person who made it. It is done very well and professionally.
I came across this diagram in another post and wanted to clarify that the shape of the WRX intake is not a ram-air scoop. I degree in mechanical engineering and we studied ram-air intakes in my fluid dynamics class. I didn't put this in engine mod section because it's not a mod, just an FYI for the community.
Although the intake isn't ram-air, it is awesome that the WRX was designed with a real cold air intake to pull air from outside of the engine from the front of the car just under the hood. Which is a great addition to the stock WRX.
A true ram-air intake has an increasing cross-sectional area, not a decreasing one. The larger cross-section slows down the air, decreasing it's dynamic pressure, and increasing it's static pressure getting denser air into the engine.
A good explanation can be found here: Ram-air intake - Wikipedia, the free encyclopedia
An example is here as shown on pro stock drag cars. Notice the smaller opening before the intake opens up to create a true ram-air effect.
-Chris
