Honda Civic Type R Exhaust Form & Function – Design Pt. 2

COMPROMISES… that’s what we have been seeing in the FK8 Exhaust Market since the FIRST Type R has been available in the USA.

From drone-filled cabins, raspy wide-open throttle, slip fitting joints, undersized piping, or a “3-inch exhaust” with a restriction section for fitment… these are compromises. The Team at 27WON Performance believed the first available Civic Type R stateside deserved an exhaust without compromises, if possible. Let us show you how we will overcome these compromises.

Before we get into the details let us acknowledge the challenges. The 2017+ Civic Type R was not an easy vehicle to develop an exhaust for. The Type R is loud, obnoxious, and drony with just a simple pipe size increase. Multiple iterations and fine-tuning of various resonator types was required to get the CTR exhaust sounding like it should, Awesome!!!

We are confident we have developed the best performance exhaust for the first Type R to make it stateside, an exhaust system deserving of the iconic red Type R badge.

True 80mm piping to accommodate future power goals

True 80mm piping to accommodate future power goals

One of the most disappointing aspects of the OEM FK8 Type R exhaust was its size.. At 60.5mm OD (2.38 inch), which happens to match the Civic SI models, the connection from the front pipe to the mid-pipe and back exhaust still restricts down to 50.5mm (1.98 inch). 

With the foresight to know that the Type R will quickly exceed the 500whp mark, we decided to design the exhaust around our own unique 76mm piping (3.00 inch). This provides more than enough headroom to support +500whp and would deepen the tone of the exhaust.

With larger piping comes more weight. To combat this we utilized custom-designed V-band flanges to keep weight at a minimum, improve ground clearance and reduce the chance of unwanted exhaust leaks.

Finley tuned side branch resonators for a no-drone experience

Finley tuned side branch resonators for a no-drone experience

Now, this is where the magic happens; where style, design, and ingenuity meet to create a masterpiece of an exhaust. There is a lot going on here; three tips, a dual-chamber pass through the resonator, and unique to 27WON our tuned Side Branch Resonators. While the components of an exhaust system must work together to create the performance and sound desired, the tuned Side Branch Resonators are the star of the show. 


The FK8 exhaust is similar to the FK7 Hatchback Sport and FC1 SI Sedan exhaust but with specific tuning for the K20C1 power plant. There are two side branch resonators for the FK8. The shorter branch is tuned for approximately 4000rpm where severe drone would occur during spirited driving. The longer branch is tuned to approximately 2900rpm to cancel out some severe drone under normal conditions. This is important when you consider the fact that the car likes to drive around this RPM range.

Our resonator placement ensure the 27WON system won’t drone you out on your commute.

Our resonator placement ensure the 27WON system won’t drone you out on your commute.

While moving to the 3.00-inch exhaust provides us the headroom for power we also got a bit more volume from the exhaust than desired. To combat this we added a large pass-through resonator to the mid-pipes. This lowered the overall volume of the exhaust note to a comfortable but exciting level without losing some of the glorious grumbles this exhaust makes.

Overall we are extremely happy with the volume and tone of the exhaust.

With the OEM downpipe, the exhaust note is noticeable but not intrusive to music or conversation. Spirited driving will wake it up but the morning commute can still be pleasant.

With a catless performance downpipe, the volume increases a good amount while the drone and rasp stay in check. This setup will get you noticed at the next show and will have you grinning ear to ear on the back-country roads and the track.

80mm V-band clamps = less hardware, zero gaskets, and no leaks

80mm V-band clamps = less hardware, zero gaskets, and no leaks

One of the key goals with the 27WON exhaust was a continuous and true 3-inch exhaust system. With this focus, we developed an exhaust that incorporates the front-pipe section with a 3.5” v-band flange and no restriction. Yes, this does mean you have to give up whatever front-pipe you might currently have installed, but it was necessary to ensure we delivered a truly seamless system.

Precise mandrel bends and fitment so you can run any aftermarket chassis braces

Precise mandrel bends and fitment so you can run any aftermarket chassis braces

We also listened to you guys and gals on the forum. The 27WON exhaust is designed to clear the mid-chassis braces that attach right where the front-pipe dumps out. Don’t worry we got you Fam.

Dual wall tips complete the beauty of the 27WON exhaust

Dual wall tips complete the beauty of the 27WON exhaust

With that we leave you to ponder our next move.  Stay tuned as we continue development of our FK8 Performance Exhaust. Sound clips to follow soon.

I DARE You to REDEFINE the Aftermarket

-Barett