February 19, 2021

-Comparison Conducted by Brian Klecker

Vehicle Specs:
2017 FFR Mk4
Coyote Engine Gen 2
Tremec 5 Speed
Mustang IRS Rearend
Approximately 3000 Miles Since Build Completion

Time Stamps:
0:35 Background Info
1:56 Exterior Sounds Levels
2:56 Interior Sound Levels
4:58 Summary Info

Brian's Background
Originally I was using the standard Stainless FFR sidepipes but found them to be very "harsh" in the tone. They were also very loud under hard acceleration which caused a lot of discomfort. Because of those issues, I decided to purchase a set of Gas-N Stainless Touring Pipes.

What I did notice was that the new Gas-N pipes had a much better tone than the FFR pipes. However, they didn't seem any quieter. I didn't do any Db readings on the FFR pipes so I didn't have a factual comparison, only that they didn't seem quieter, even though they did sound much better.

At this point I contacted Georgie and found out that by accident, I ended up getting a set of the normal Gas-N pipes, not the Touring Pipes I had ordered. Georgie said to use the pipes until the new Touring Pipes arrived and then switch them out and send him back the other set (Great Customer Service).

Georgie asked me to get a reading on the sound change between the current "normal" pipes and the quiet pipes for him with a Db meter. I agreed to do that but being a bit of a geek, I wanted to do a bit more and be "reasonably" scientific about it.

So this video is MY comparison of the Gas-N Standard Side Pipes vs the Gas-N Touring Side Pipes, on the same car/engine and under nearly the same conditions. I wasn't paid by Gas-N to do this or endorse his product. I paid full normal price for the pipes like anyone else.

At the end of the day I really like the Gas-N Quiet Pipes and wholeheartedly appreciate the great customer service I got from Georgie. I hope you enjoy this presentation and it helps you make a decision on what pipes you’d like for your Cobra.

Exterior Sound Levels
Db Meter was located at a 45 degree location to the back right of the car at 15' from the pipe tip. Looking for Peak Db reading.

RPM - Regular / Touring
800 rpm (Idle)  -  89.5 / 83.0
1000 rpm  -  95.0 / 84.5
2000 rpm  -  98.6 / 95.0
3000 rpm  -  106.7 / 99.4
4000 rpm  -  109.8 / 105.9
5000 rpm  -  114.1 / 109.7
6000 rpm  (2 sec WOT)  -  123.8 / 111.6

Interior Sound Levels
Setup: the Db Meter was located on the dashboard to minimize wind noise. I also connected a microphone to my phone and located it next to the Db Meter which you can see in the video.
I tried to cause similar driving situations with both sets of pipes so that you can hear the interior sound differences.

Peak Db Readings - Regular  / Touring 
Idling  -  88 / 79
Casual Driving   -  116 / 104
Fast Acceleration  -  119 / 106

Summary:
Gas-N Regular vs Touring Pipes Average Reduction in Sound Levels = 10 Db
(Interior or Exterior Reduction)
FFR Mk4 with a Coyote Gen2

The Touring Pipes don't seem to loose much of the exterior loudness we like with our Cobras. But on the interior you gain a huge amount of liveability comfort for overall driving and being able to carry a conversation with a passenger.

After putting on the Touring Pipes my wife no longer felt the need to have earplugs the whole time we were driving. We just finished 3 days of driving where we drove over 700 miles, everything from a slow cruise in cities, to highways speeds and steep curvy mountain roads (Tail of the Dragon).

The Touring Pipes made the trip much more enjoyable in all driving conditions!