Flowmaster break in period?

[slayerripkdc]

Just installed my 40 series with stock H. I realize the stock cats will quiet things down a bit. Do they usually get a little louder after a few hundred miles or what? Can't wait to install my O/R H .

 

[Jacob_Royer]

Flowmasters are quiet with stock cats. OR pipe FTMFW! before my xpipe my flows where no louder than the stock mufflers!

 

[slayerripkdc]

You have American Thunder mufflers. I have the 40 series. I think the 40's are a tad more throaty then the AT'S. I could be wrong.

 

[Deleted member 38176]

You have American Thunder mufflers. I have the 40 series. I think the 40's are a tad more throaty then the AT'S. I could be wrong.

The AT kits uses 40-series muffs

 

[BlownFiveLiter]

Flowmasters don't have any packing inside of them that will "break-in," so what you hear is what you get. Lose your cats and you'll really hear a difference, as Jacob Royer mentioned.

 

[ItsStock02]

My car came with flowmasters welded in the stock cat back. With the stock h-pipe it sounded like a stock Mustang, but it was slightly louder. I liked how it sounded, but i like how it sounds with my o/r prochamber even more.

 

[joshwfl]

I have an o/r H with 40's and it sounds sweet. Lots of crackling on decel, much louder than the vid makes it seem. Not everyone likes it, I love it!

YouTube - 2000 Mustang GT 5 speed H pipe, cat delete, dual 40 series Flowmaster

 

[westgastang5.0Coyote]

As everyone else said what you see with them right now is what you get. But a o/r prochamber is one of the best combos i've heard with flows.

 

[slayerripkdc]

American Thunder does not come with the original 40 series, they come with super 40's. They are a little more mellow.

 

[68stang351]

You have to get rid of that mid pipe.

Here's my 04 with off road x and flowmaster 40's.
YouTube - My 04 GT


My buddie's 01 with the same mufflers but with a off road prochamber.
YouTube - 01 Gt mustang

 

[Twista]

Sorry, bud. I went through this before but with a mac aftermarket hi flow catted H pipe. It was stock quiet... it pissed me off so bad. SO SO SO bad. I added a o/r prochamber and the car woke up so much. I then added a mac o/r H and boy it was loud.


What you hear now.. is the sound your going to keep unless you change the midpipe

 

[GettinThere]

I have an o/r H with 40's and it sounds sweet. Lots of crackling on decel, much louder than the vid makes it seem. Not everyone likes it, I love it!

+1000 The crackling sounds so juvenile

The drone was a bit annoying, but the 4.10 gears somehow reduced that.