K-Tuned 4-2-1 K-Swap Header 92-95 Honda Civic EG / 96-00 Honda Civic EK / 94-01 Acura Integra DC2 / 88-91 Honda Civic EF - 409 Stainless Steel

Item SKU: KBH-421-409-SS

K-Tuned's K-Swap Header 4-2-1 in 409 stainless is made for K-swapped 1992-1995 Honda Civic EG, 1996-2000 Honda Civic EK, 1994-2001 Acura Integra DC2, and 1988-1991 Honda Civic EF chassis. On an EF, the subframe needs a slight notch for clearance. This is the 4-2-1 layout for a K20 or K24 swap, with the routing centered through the exhaust tunnel and clear of shifter mounting kits.

• Material and build: Full 409 stainless-steel construction with TIG-welded tubing, CNC-cut flanges, and thick 3/8-inch flanges that are double welded and ported.
• Tube sizing: 45mm OD primaries feed 47.5mm OD secondaries. The expanded secondary joints and collector transitions are designed to avoid a step where the pipes come together.
• Flex and outlet: A 2.5-inch ID interlocking flex section handles engine movement and heat. The outlet uses a 2.5-inch, three-bolt flange.
• Sensors: Two oxygen-sensor bungs are included, so you've got provisions for the sensors your swap requires.
• Mount compatibility: Hasport EKK1 and EKK2 mounts work with this header.

This stuff is built around the practical parts of finishing a K swap: keeping the header in the tunnel, leaving shifter hardware alone, and giving you a standard 2.5-inch three-bolt outlet to tie into the rest of the exhaust. Exhaust welding is required during installation, so plan the header and exhaust connection together rather than expecting a fully bolt-on finish.