Product Description

Designed specifically for the new Focus RS platform. State-of-the-art CFD simulations and rigorous flow analyses are standard for all BIG MOUTH products.

The Focus RS is no exception. The Focus RS BIG MOUTH ram air kit features an industry first, customizable airbox seal. This seal partitions the airbox from the engine bay, allowing the BIG MOUTH to feed higher pressure air into the airbox without losing air mass or pressure to the engine bay. During idle conditions, your airbox will not ingest hot engine bay air. The seal comes with a soft rubber strip that mates to the entire perimeter of the open hex area of the airbox. This creates the air tight seal and allows your BIG MOUTH to function as intended.

If you wish to buy just the BIG MOUTH duct and do not need the seal, select NO in the drop down menu for the airbox seal option.

Choose the colors of your BIG MOUTH body, inlet flare and seal. Pop the hood and everything matches as if it was OEM! If you were looking for that best-bang-for-your-buck modification for your Focus RS, this is it. Get aerospace level performance, award winning design and a proven track record, don’t look back.