GReddy DD-R Catback Exhaust | 2017-2021 Honda Civic Si Coupe (10158600)

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$940.50 $990.00Instant Savings of 5% ($49.50)

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2017-2021 Honda Civic Si Coupe DD-R Exhaust System by GReddy

With our distinctive style and design, the Greddy Performance Products DD-R is our modern take on the highly-sought after GReddy DD Dynamic Dual€� exhaust of the past.

Our iconic DD exhausts have always been recognized for its aggressive dual exit look and deep GReddy sound, but with this new DD-R, we also incorporated updated and improved full 304 stainless-steel construction.

The GPP DD-R has been adapted to modern tuner cars to not only enhance the looks and sound, but to improve performance with its carefully designed dual high-flow straight-through muffler layouts. Another new feature on the DD-R is the tunability. With the new twin removable tips, new options for tips finishers and silencers, now allow the owner to fine tune the looks, sound and flow of their DD-R.


  • Full 304 Stainless Steel Construction
  • 3" High-Flow, Straight-Through Design
  • Dual Muffler Layout w/ Twin Tips
  • Tips Are Removable For Future Customization


  • 2017 - 2021 Honda Civic Si Coupe

What's In The Box?

  • 1 - GReddy DD-R Exhaust System


  • GReddy Limited Lifetime Warranty

Customer Reviews

Based on 7 reviews

Love the sound!

Sounds great!

Shipping was fast, it came in less than a week from time of order. And the GReddy DDR itself sounds really good on my Si. Everything without a flaw and packaged nice along with the hardware. The tone and growl of it in idle is dope, and the gurgles it gives when the RPM Drops is sick!


Best sounding exhaust. Low growl

Greddy DDR

Sounds amazing awesome that they price matched good people at MAP just got into the car game this year and have already bought 5 things from these guys def will be buying more in the future probably.

steve thao

the exhaust is amazing on my 2019 coupe si. its the only mod i have at the moment. it looks good. sounds good. feels good.

however installation was just a little annoying. connecting to the oem front pipe is hard to do. i had to use the nuts and studs from the oem front pipe to connect it to the catback. the only problem is there isnt that much “tightening space” for the nut since the flange for the greddy exhaust is a little big. the stud doesnt go through the nut all the way.

otherwise its awesome.