Improving or Replacing a Magnaflow Exhaust.

[Swenster]

Hello, I recently purchased a 2019 Fiesta ST with around 75k miles. It has a Magnaflow catback exhaust on it currently. It sounds decent up to around 55 MPH but then begins to drone. I like an exhaust that pops and gurbles but not a fan of the drone. Is there a means to improve the Magnaflow or is it best to entirely replace it with the Thermal R & D exhaust? If best to replace, is there a recommended merchant? I may need to bite the bullet but wanted to see if there was any other proven option vs replacement. Please let me know and thank you. The dealer also included the K and N cold air intake they removed from the car. I will likely reinstall it at some point.

 

[foodtruck]

Hey, welcome to the forum!

I think the default recommendation for Fiesta ST parts in US is Whoosh motorsports. Properly reducing the drone is possible but probably time consuming to design and you'll need to find a shop that will take up the work, see https://www.fiestastforum.com/threa...e-current-quarter-wave-resonator-setup.19544/

Sounds like not something you might go with, but another budget option is to get a second hand stock exhaust in good condition.

 

[Tyrre]

Hello, I recently purchased a 2019 Fiesta ST with around 75k miles. It has a Magnaflow catback exhaust on it currently. It sounds decent up to around 55 MPH but then begins to drone. I like an exhaust that pops and gurbles but not a fan of the drone. Is there a means to improve the Magnaflow or is it best to entirely replace it with the Thermal R & D exhaust? If best to replace, is there a recommended merchant? I may need to bite the bullet but wanted to see if there was any other proven option vs replacement. Please let me know and thank you. The dealer also included the K and N cold air intake they removed from the car. I will likely reinstall it at some point.

if your main goals are to keep some pops and burbles while completely eliminating highway drone, replacing the Magnaflow is usually the cleanest and most reliable solution. On the Fiesta ST platform, the Magnaflow catback is well known for droning around steady-state cruising speeds, and while it sounds good under load, that resonance tends to be baked into the system’s design.

 

[Tyrre]

if your main goals are to keep some pops and burbles while completely eliminating highway drone, replacing the Magnaflow is usually the cleanest and most reliable solution. On the Fiesta ST platform, the Magnaflow catback is well known for droning around steady-state cruising speeds, and while it sounds good under load, that resonance tends to be baked into the system’s design.

Exhausts like the Thermal R&D are engineered specifically to cancel those frequencies with multiple resonators, giving you a deeper, smoother tone at cruise while still being aggressive when you get on it.