AFE Power part # 48-36602-HC is a Twisted Steel Down-Pipe (street) that fits 2012-15 Honda Civic Si 2.4L. The street version down-pipe (shown in pic) is designed using a 48-state legal 400 cpsi catalytic converter and mandrel-bent, 304 stainless steel tubing for optimum flow resulting in added horsepower and torque. This down-pipe is 100% hand TIG-welded and uses a 2-3/4" into 2-1/2" stepped design that increases exhaust velocity and eliminates low pressure drops which helps to scavenge the exhaust for increased power. +8 horsepower and +7ft. lbs. of torque.
For race version without catalytic, use part # 48-36602-HN.