Stock GT muffler mod

[stevens11bravo]

How to modify a set of stock mufflers to flow like GT500's. Picture shows dual outlet GT500 muffler but from what I'm told the single out version is the same with one less outlet. I have a sound clip after the mod (I should have done a before and after but didn't think about it until it was finished but I'm sure you can find some stock exhaust videos). http://www.youtube.com/watch?v=SudepXqRWd0

 

[stevens11bravo]

Lets try uploading the pics again

 

[DSG2003SVT]

Let's see that sound clip. Way to go on the budget modification!

 

[stevens11bravo]

Mustang GT oem muffler mod - YouTube

 

[kevin2970]

Wow! That actually sounds really nice. Awesome work man.

 

[charba951]

That's pretty good!

 

[FiveSlow]

Jesus. That's pretty ingenues. Good job. You should sell modified stock muffles, could be a nice little nitch market to make some future mod money.

 

[PIKE5.0]

I'm over my outlaws.. Think I'll give this a shot along with putting some 4" tips if possible. Just hack the hell out of these stockers lol

 

[stevens11bravo]

Thanks guys. I'm glad everyone seems to like these. I'm sure with a offroad mid-pipe they will sound awesome (I plan to test a pair with long tubes and a off-road x within a few months). I also have a set of 4" double wall tips I plan on putting on another set I just modified. The pair pictured was just a old pair I wanted to use for R&D.

 

[May93]

Way to build a one of a kind exhaust!

 

[stevens11bravo]

Well guys I picked up another set of stock mufflers to modify and did them slightly different. I didn't take photo's but did change the illustration on the stock muffler cutaway to show you exactly what I did. This design gives them a larger chamber in the middle for the main flow path and provides more flow into the other chambers for a slightly deeper/mellow tone but still similar in sound to the first pair. Just so no one asks, the car was completely warmed up for both videos, lots of steam due to the 20 deg. weather. http://www.youtube.com/watch?v=nms8Nw3wd4c

 

[jakhammer]

Do you have any driving vids? Im impressed so far. Nice work!

 

[TorchedMach]

How's the interior resonance?

 

[Tomcat5157]

I will be trying this tonight. Trying to save a little money until I can buy my exhaust and this way sounds perfect.

 

[stevens11bravo]

Interior resonance was not much different than stock. Sorry, I didn't get any driving videos. I installed long tubes and a offroad x. These mufflers got a little raspy sounding with that setup but sounded wicked in the upper rpm range. I didn't get any vids of that setup as it wasn't on long. I now have the LT's, X, and a Magnaflow competition catback with resonators added to the ota pipes.

 

[Nuar]

I had no idea what to expect, but to be honest, the modified stock mufflers sounded pretty damn good! Awesome mod for someone that has welding skills and doesn't want to spend a lot on mufflers right away.

 

[Tomcat5157]

I did this as well as had my resonators cutout. sounds amazing! no resonance while cruising on the highway but it sounds like a mustang should when you get on it. im installing cat deletes tomorrow so well see how that goes.

 

[3unn]

I had my car up on the lift at work to clean the undercarriage today and decided to try this out. I have successfully modified factory mufflers in the past with excellent results. I was planning on doing the GT500 twin tip and valance but this was free minus 2 hours of my life, 2 zip cut discs, some mig wire and welding gas. I will likely still do the GT500 twin tips i the future because I love the look. First time I turned a wrench on this car with only 1,600 km's on it.

I opened the outlet tube of the muffler to the chamber where the inlet dumps into. I did not weld the smaller tube shut that normally is the only path between inlet and outlet. I also removed a substantial amount of the fiberglass packing in the outlet tube. I could not be more pleased with the results. I love the volume of the exhaust on the outside but at times I wish it was louder inside the car. I am glad however that these cars are very quiet inside.

I'll post a sound clip when the weather is nicer.

 

[Vert]

I think I am going to try this out next weekend. Curious if the OP removed all of the fiberglass or just partial amount like you did.

I had my car up on the lift at work to clean the undercarriage today and decided to try this out. I have successfully modified factory mufflers in the past with excellent results. I was planning on doing the GT500 twin tip and valance but this was free minus 2 hours of my life, 2 zip cut discs, some mig wire and welding gas. I will likely still do the GT500 twin tips i the future because I love the look. First time I turned a wrench on this car with only 1,600 km's on it.

I opened the outlet tube of the muffler to the chamber where the inlet dumps into. I did not weld the smaller tube shut that normally is the only path between inlet and outlet. I also removed a substantial amount of the fiberglass packing in the outlet tube. I could not be more pleased with the results. I love the volume of the exhaust on the outside but at times I wish it was louder inside the car. I am glad however that these cars are very quiet inside.

I'll post a sound clip when the weather is nicer.

 

[3unn]

I almost don't want to post the video because it doesn't actually sound the same in person. I mean I know a recording never does justice to an exhaust but this is actually strange. I had a friend rev it and do a drive by and it sounds eleventybillion times better.

http://youtu.be/g-TXEOKlA8k