ICONIC K-SWAP 4-2-1 EXHAUST MANIFOLD FOR K20 K24 EK CIVICChanging the manifold is one of the best modifications you can do to your K swapped Honda. Just with this alone, gains of between 5 10bhp are achievable before mapping. With supporting mods and mapping, gains of between 7 15bhp and a lot more torque are easily achieved. Constructed from premium 304 grade stainless steel our exhaust manifold features the popular 4 2 1 design. Being a 4 2 1 configuration means it gives both excellent mid range and good