Neither replaces the air box. The Roush just uses an open lid that's supposed to seal to the hood. The factory air box lid is fine but running any open ended filter allows for more hot air into the engine vs the Ford Racing intake that pulls fresh colder air from the high pressure area of the front grille. I like this combined with the Mountune low loss crossover piping personally.Seems to me the only difference between the two are about 30 bucks and with the cobb you replace the factory flex fitting but keep the factory airbox. While with the Roush, you keep the fitting, and replace the box? so Which is optimal?
That's over paying for everything. The green filter does not come with a plug. They will sell you one for under $20.so are these green filters all close ended ? Seems like everyone is running an open-ended filter no? and the 600 comes from cjs; the ford racing intake is 233 and the mountune intake is 370 ..603..