There are several neat things about Imprezas. One neat thing is that you can buy race prepped versions from the factory. The Subaru Impreza WRX STI Spec C Type RA-R is a nice one. It's even better if you know what all the letters mean.
The important one here is 'C' for 'Competition'. A *normal* competition package means A/C delete. Cars without A/C get hot, so that's why they get a roofscoop. The factory cars get a roofscoop that folds flat when not used. The big fixed roofscoops mount over the inside scoop and are usually open at the rear. Some race roofscoops I've seen are full carbon fiber and have a false floor built into the outer scoop to keep out rain and drain tubes to get rid of the water.
I'd love to see more race homologated production cars like the WRX, but I won't hold my breathe. If there was a production-based race series for high fuel mileage, we'd see some real wild cars.
For example, Toyota is slated to make a RWD small car using a Subaru flat 4. It's supposed to be a spiritual successor to the AE86 Corrolla hatchback (the Hachiroku). Subaru offers a turbo-Diesel flat 4 in Europe. Combine those ideas and you get a slick little 2 door Diesel coupe.
