What is the main difference between a resonated and non-resonated exhaust?

A resonated exhaust includes a chamber designed to cancel out specific sound frequencies, often reducing drone and making the exhaust note smoother. A non-resonated exhaust typically has a louder, more raw sound without this frequency management.

Does this exhaust system require welding or cutting?

No, this GReddy cat-back exhaust system is designed as a bolt-on replacement for the factory exhaust from the catalytic converter back. It includes all necessary hardware for installation without requiring cutting or welding.

What is the expected sound difference from the stock exhaust?

This resonated cat-back exhaust is expected to produce a sportier, more aggressive tone than the stock exhaust, particularly under acceleration. The resonated design aims to keep it from being overly loud or droney during normal driving.

GReddy DD-R Resonated Cat-Back Exhaust 10158600

Name: GReddy 2017+ Honda Civic SI Coupe DD-R Resonated Exhaust
Brand: GReddy
SKU: greddy-greddy-2017-honda-civic-si-coupe-dd-r-resonated-exhaust-t14-344253
Price: 1013.76 USD
Availability: BackOrder

GReddy 2017+ Honda Civic SI Coupe DD-R Resonated Exhaust

$1013.76

On Backorder — Expected to ship by Aug 9, 2026

Order now to reserve yours — we'll ship as soon as stock arrives. Full refund if we're unable to fulfill.

GReddy 2017+ Honda Civic SI Coupe DD-R Resonated Exhaust

Key Features

Fits 2017+ Honda Civic SI Coupe.
3-inch diameter, mandrel-bent stainless steel tubing for smooth exhaust flow.
DD-R resonated muffler design aims to reduce drone while enhancing exhaust tone.
Straight-through muffler internals minimize backpressure for improved engine breathing.
Dual-tip exit provides a sportier rear aesthetic.
Includes all necessary hardware for installation.

This cat-back exhaust system is designed specifically for the 2017 and later Honda Civic SI Coupe model. Please verify fitment for your specific vehicle.

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Product Details

Constructed from 3-inch diameter, mandrel-bent stainless steel tubing, this GReddy DD-R resonated cat-back exhaust system is built for the 2017 and later Honda Civic SI Coupe. It's designed to replace the factory exhaust from the catalytic converter back, offering a more aggressive sound and improved exhaust flow compared to the stock setup. The resonated design helps to manage drone and unwanted frequencies, aiming for a sportier tone without being overly intrusive during daily driving.

The DD-R (Dual Drive-R) muffler features a straight-through internal design, which minimizes backpressure and allows the engine to breathe more freely. This can lead to a noticeable improvement in throttle response and a more engaging exhaust note, especially when the engine is under load. The system includes a dual-tip exit, giving the rear of your Civic SI Coupe a more performance-oriented look. All the necessary hardware for installation is included, making it a straightforward bolt-on upgrade for those looking to enhance both the sound and performance of their vehicle.

When installing this system, you'll want to ensure all connections are properly sealed to prevent leaks. The stainless steel construction means it's well-built to resist corrosion over time, even in varied weather conditions. This cat-back exhaust is a popular choice for Civic SI owners looking for a balance between a sportier sound and a refined driving experience.