NASCAR has mandated a new spoiler for all the Cup cars as of the last race at Martinsville. The teams must purchase this spoiler from an approved vendor, it must be black, and the teams are not allowed to put any branding on it.
As was the case with the now-banished rear wing there is a mandated “roof strip” or “roof rail” on both sides of the car that runs from the top of the front windshield to the top of the rear window. The height and thickness of the roof strips are mandated by NASCAR, but teams construct and mount their own in compliance with the NASCAR Sprint Cup Series rule book.
New with the re-introduction of the spoiler on Sprint Cup cars are two stationary air deflectors on the driver’s side of the car only. One runs from the top of the rear window and runs the length of the rear window, aligned with the left side roof rail. The height of the deflector will be mandated by NASCAR depending the track – short track, intermediate or superspeedway. The second air deflector runs the length of the “trunk” deck lid. Length variation and height variation will be mandated by NASCAR. Teams will construct and mount both air deflectors per provisions in the rule book. They are painted in the scheme of the car and no branding is allowed. The teams have nicknamed them dolphin or shark fins.