Edelbrock designed this header for Honda/Acura engines, including JDM-spec engines. The header was extensively R&D tested on many well-known daily driven 12-second all-motor cars as well as 11-second naturally aspirated race vehicles. On a stock motor, you'll see gains of 6-hp at the wheels with the stock cat-back exhaust! With the optional race B-pipe, this header has supported well over 250-hp at the wheels! All the flanges are laser cut 3/8'' stock that is then CNC-machined for a precise fit. The header is a two-piece design with 1-3/4'' diameter A-section and a 2'' diameter B-section that hooks up to the exhaust system. A optional 3'' diameter turndown B-section, which will help lower E.T.'s, is available for drag racing.