Mann & Hummel Automotive (www.mann-hummel.com) has developed Top-sys, a continuously variable induction system incorporating all components from the fresh air inlet through to the cylinder head. Extensively tested on production vehicles, the system has yielded impressive results including decreased fuel consumption up to 3%, reduced noise levels up to 8 decibels, decreased pressure loss of 38%, and a 10% increase in volumetric efficiency. It can achieve the same overall results as variable valve timing, however, with cost savings of approximately 20%.