Modified Mustangs & Fords Completely Unscientific Muffler Test

While in Birmingham celebrating the Mustang 45th we saw Ford Racing installing a lot of parts. From cold air kits to rear gears to mufflers they were busy all weekend. The most popular muffler being sold was the 5230S muffler. This is the muffler that comes stock on the FR500S Mustangs used in the Mustang Challenge for the Miller Cup series. To find out how good they sound compared to other mufflers we had Ford Racing send us a pair to give them a completely unscientific test.

The 5230-S mufflers are bullet style mufflers that are made from aluminized 409 stainless steel with polished 304 stainless 3.5-inch tips. They feature the Ford Racing logo stamped on the body so it shows when viewed underneath the car.

For our tests we compared them to stock Mustang GT mufflers as well as the SVT1 mufflers that are stock on the GT500. The Mustang in question is stock save for the cold air kit. We didn't dyno test them as Ford Racing claims no power gains in HP or torque. While others have seen gains, Ford Racing saw none in their tests, so we'll go with that. Your mileage may vary, as always.

To test them we setup a decibel meter 20-feet behind the car and got readings at idle, 3000RPM and 5500RPM. We also did a driveby sound test at 4500RPM. For the highway driving test we skipped the sound level test as road noise is the norm, especially with 3.55 gears. What we looked for was the drone that most mufflers suffer from.

So, lets see make some noise! And maybe some power too!

Whats the final verdict? With a great throaty sound and a definite aggressive tone the 5230S mufflers are, in our scientific opinion, the best of these three choices.