Flowmaster Resonating Bad

[rob41185]

hey i got a flowmaster installed and when i get around 2500 rpms i get horrible resonance inside my explorer. Is there anyway to fix this? Do you guys think a bigger tip might change the sound and thus get rid of the resonating? Oh ya, and the piece of crap tip i got is rusting after about a week. That can't be normal... THanks for the help

 

[Alec]

What model muffler did you get, what motor do you have, and what size tailpipe did you get?

And where does it exit?

 

[tbomb]

well if its a "piece of crap tip", then im sure its reasonable for it to rust after a week.

the size of the tip wont make a difference with resonance, unless you buy one of those tips that some ricers get, itll make it a lot worse.

theres really nothing you can do about the resonance; its the nature of the "cat back" beast. thats why i went through 3 or 4 different cat backs in one summer and ended up going back to stock. when you install a muffler with less chambers in it to dampen the noise, youre increasing the allowable flow through it and, in turn, the exhaust system will make a helluva lot more noise. having a v6 doesnt help - personally, i dont think they sound very good with exhaust (theyre very high pitched, squeely, and they resonate like hell), but thats just me

 

[CougarX]

Mine does it real bad, but i've learned to live with it, and i love the sound of my flowmaster 50 and i don't think i would trade no interior noise to get rid of it.

 

[rob41185]

exhaust setup

its a flowmaster 40 series delta, single 2.5 inch pipe out back. The tip is a 2.5 inch chrome one. I think the reason why the tip is rusting is because one of the guys at the shop made the end of it bigger so it would fit over the 2.5inch pipe and doing that caused the chrome finish to crack. I was thinkin that a 3inch tip might change the sound just a little bit...enough to get rid of some of the interior resonance at 2500rpms. Other than that little spot, there isn't any real bad interior noise.

 

[rob41185]

oh its the 4.0sohc

 

[james t]

the only way to help it is to go down in tip size, not up. and even then, it wouldnt make that much difference. thats just what a 40 series does. sorry.

you think yours is bad, i have one on my 5 liter and it dumps near the rear end with no visible exit. its louder inside the truck than outside.

 

[Alec]

Well, you got the 40 series, which is inherently loud. Sorry, but you just chose a loud muffler.

A larger tip probably won't change the sound, though a slash cut tip may reduce the resonance a bit. If the tip is too large and too long, you may get more resonance.

Maybe you can have them add a resonator after the muffler to smooth out the airflow. My resonators were only about $20 and I have one before and one after the muffler. I need them on mine because I have 3" pipes for max flow at WOT. At less throttle it sounds bad without the resonators.

Oh and a tip that the chrome can crack and rust is still a crappy tip, even if the guy messed with it.

 

[rob41185]

resonator

Will a resonator distort the sound of the muffler? I still love the way it sounds and im only trying to get rid of that horrible sound at 2500 rpm. Some have said that a resonator would distort the sound and i want to keep the rumbly sound i have. Thanks

 

[Alec]

It might, it might not. My resonators do change the sound, but they turn it from having a little bit of bumble-bee to more of a roar.

I think the best thing you could do is get a Flowmaster 50 delta.

 

[rob41185]

thats what i wanted

i actually wanted that as my first choice but the shop couldn't seem to find one and at the time i didn't think it would be much louder but i was wrong.

 

[Nate1]

One thing you can do that *might* help is apply some dynomat extreme along the undercarrige of your car along the exhaust path. I have a '99 SOHC I know know exactly the resonace you are talking about. I think it is just our motors, you can learn to live with it. Try dynomat and a resonator, or move to the 50 delta.
Thats what I would do...
-----Nate