While the horsepower wars continue, automakers are searching elsewhere to see where precious time can be shaved off of a hot lap. Porsche, in particular, is looking to redefine the rear diffuser. New ...

We gave our F90 BMW M5 a rear-end refresh with a sleek RKP carbon fiber diffuser and a clean Acexxon reflector delete for that perfect OEM+ look. 💨 Watch the full install and see how these subtle ...