Our merge collectors, with a secondary transition, offer optimal performance by increasing exhaust velocity through the merge area and then takes advantage of the exhaust charge expansion after the merge. This acts like a syphoning effect that greatly increases exhaust scavenging. Available in a variety of primary inlet, merge and secondary sizes, these merge collectors are handmade using American made bends.Engineered to obtain the high flow and velocity only available in a true merge collectors, every unit is purge tig welded and incorporates a transition spike that is internally blended. This internal blending and spike design, makes the transition from the primary tube to the collector, as smooth as possible. This smooth transition maintains exhaust velocity, improving volumetric efficiency.