Vibrant 4 1 SS Merge Collectors (1 7 8in Inlet Slipover ID 2 1 2in 2 1 Stainless SS Exhaust Merge Collector Dual 2" ID Inlet Single 2.5 Vibrant for 2 1 SS Merge Collectors (3in ID Inlet X 2 2.5in ID Outlet Vibrant Performance 10303 VIB10303 4 1 S.S MERGE COLLECTORS (1.75IN Turbo Merge Collectors. Vibrant Performance has developed a comprehensive, high quality and Affordably priced range of 304 Stainless Steel Merge Collectors to help our customers free up maximum horsepower from their exhaust setup. For many years, merge collectors were almost exclusively used by top professional race teams. However, this proven technology is now commonly used at all levels of professional racing (where rules permit) and now many fabricators are incorporating merge collectors into street header applications.