For those that choose ease of maintenance along with performance gains, the single 40 HPMX is the set-up of choice. For the basic 1600-1800cc, the 40 HPMX Kit is a torquey option. EMPI also has available a selection of jets if your application requires further dialing in. 40 HPMX Carbs have butterflies drilled for smooth idling. Complete kits feature Aluminum Center-Section Manifold, Aircraft Style Heim Joint Linkage, Chrome Air Cleaner with gauze element, gaskets and hardware. Complete with detailed illustrated instructions and attractive EMPI packaging. Fits Type 1 1600cc based upright engines.