HKS Sport Cat-Back Exhaust for 07-08 Civic Si Sedan

HKS Sport Cat-Back Exhaust, 65mm for 07-08 Honda Civic Si Sedan (FA5) K20Z3

Plenty of aftermarket exhausts for the Si are loud. Great at full throttle, tiring on a 40-minute commute, and the drone at 70 mph gets old fast. The factory system goes the other way. It's quiet and restrictive, and the K20Z3 never really sounds like the engine it is. HKS's Sport cat-back sits in between. It's made for an Si sedan that gets driven every day: a little more voice and a little less restriction, without making the car obnoxious.

So what changes? The sound gets fuller and sportier, especially as you get into VTEC, and it settles back down when you're cruising. You'll pick up a little flow, but on a stock K20Z3, a cat-back alone is worth a few horsepower at most. You'll hear the difference more than you'll feel it. If you want the Si to sound like it means it without getting looks at every stoplight, this is the one to get.

65mm Pipe, 120mm Titanium Tip

The system runs 65mm piping from the cat back, which is plenty for a naturally aspirated K20 and leaves room if you add a header and tune later. It finishes in a single 120mm titanium tip. Titanium picks up blue and purple heat colors over time, so the tip looks a little different on every car. The stainless body is fully coated, so it holds up to road salt and grime.

Everything You Need in the Box

HKS includes all the hardware and gaskets, so you're not running to the parts store halfway through with a bolt that doesn't fit. On a car this age, the factory bolts at the cat flange are usually seized. Soak them with penetrating oil the night before. Hang the system loosely on the factory hangers, center the tip in the bumper, then tighten from front to back. Once it's warmed up, check for leaks and rattles.

Fitment

• 2007-2008 Honda Civic Si Sedan (FA5) - K20Z3
• Does not fit the 2009-2011 Civic Si Sedan
• Does not fit the Civic Si Coupe (FG2) or non-Si Civics
• Hardware and gaskets included