Fugly. heh heh. I like it a lot. You would definitely look like a complete ******* with a non-functional roof scoop. Well, it could function as an air brake, but you'd still be a *******. Same goes for fake hood scoops. And fart cans. If you want a cool car with scoops and a throaty exhaust note, save up for a F1 Ltd. If you want your car to be cool don't pose; go subtle and get some forced induction and wipe your cars butt with some upitty ricers.
hmm my guess is on the McLaren its got a sort of runner for the air to hit the engine look at the picture (this is an accurate model) the roof scoop seems to take in air then vent it to the engine judgeing by the back of the car I could be wrong
On the WRC Focus and the WRC WRX they are used for high speeds. When they are going so fast that the scoop on the hood does not get any air this is where the one on the roof comes in. It will pick up the air and send it the engine. I think I heard this from WRC on the Speedvision. Also I think there is one for cabin air. I could be wrong. Does this make sense to any one else?