AFE Twisted Steel Down-Pipe w/ Cat Street For 12-15 Honda Civic Si… 48-36602-HC

This race down pipe uses a unique resonance chamber to capture sound waves and minimize in-cab resonance producing an aggressive tone on throttle with a smooth sound at cruising speeds without effecting performance. In recent testing, the race version down pipe produced +14 horsepower and +39 lbs. x ft. of torque. The high-flowing down pipe is designed using mandrel-bent, 304 stainless steel tubing for optimum flow resulting in added horse power and torque. The down pipe is 100% hand TIG-Welded and uses a 3-1/2" into 4" stepped design that increases exhaust velocity and eliminates low pressure drops which helps to scavenge the exhaust for increased intake charge and more power.