AFE Mach Force XP Diesel Exhaust Systems and filters are very good at getting air to your engine faster and more efficiently. However, we realize that it is important to get the air out as well. Just like anything else, the more you ingest, the more you need to expel, otherwise things can get clogged up. That is the reason why we offer exhaust systems to go along with our air intake systems. It is a natural extension of our efforts to enhance the science of airflow management in performance vehicles. This is especially true in the diesel motor which is simply a huge air pump. Since diesel engines are a compression ignition engine and modern diesel-powered vehicles are turbocharged, the more air you pump in, the more power you generate.