Embracing the legacy of the iconic Civic Si coupe, the GReddy Supreme SP exhaust system is a tribute to the storied SP line with its signature fitment and deep, robust sound. This latest iteration stands out with its larger 2.5-inch (63.5mm) piping, an enhanced resonator, and an upgraded muffler—all designed to maximize performance and acoustic richness. Compatible with both the coupe and sedan Si models (sedan requires the optional 11050104 adapter), this cat-back system is a testament to GReddy's commitment to quality, sporting a new Limited Lifetime Warranty. As with all GReddy exhausts, the Supreme SP is a hand-welded masterpiece, crafted from premium 304 stainless steel, ensuring reliability and longevity.

Make: Honda Model: Civic Si 2dr. (4dr with adapter p/n 11050104) Years: 2006-2009

Options: Si Coupe, Si Sedan with 11050104 adapter

Chassis: FG2

Engine: K20

Type: Performance Cat-back Exhaust

Components: 3-piece system

Piping: 63.5mm (2.5")

Tip: 102mm (4.0")

Gaskets: 2.5" oval (2 included)

Resonator: Included

Weight: 27.5 lbs (slight increase over stock 27.3 lbs) Sound Level: 90 dB(a) Performance Increase: +5 hp, +3 ft-lbs torque