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Plead The First
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Discussion Starter · #1 ·
I already have a Magnaflow muffler, 22" I believe, and it's got some bad resonance from about 1500 to 1900 RPM. It's placed right where the stock one was, if I move it backwards or forwards or even rotate it would it decrease the resonance? Any ideas would be great.
 

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thats right
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no that wont really help at all. what size piping? same size as the muffler outlets?

resonance is really part of the magnaflows. they are WAY overhyped. i had one an hated it.
 

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Plead The First
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Discussion Starter · #4 ·
What would you suggest? I don't have the money for a corsa so I just need something to go in it's place.
 

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thats right
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lol i dunno man. i never really tried to fix mine, i just put the corsa on.

maybe you can try a resonator? or swap in a diff muffler. i had a dynomax race series(12 inch long case x 9 inch wide) on my 94. it was a straight through design just like magnaflow, but it had zero resonance. i was shocked that the magnaflow resonated so much when it is supposed to be the same as the straight through dynomax.

is yours dumped? or full tail?
 

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Plead The First
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Discussion Starter · #6 ·
It's all way to the back, but hidden. I think I'm going to mess around with it tommorow see if I can get any improvement.
 

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thats right
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i might be wrong, but i THINK that a dump right after the muffler could reduce the resonance. i was going to try that on mine before i got the catback
 

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HOT AIR BALLOON OWNER
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I dunno, I have a 5x11x22 on my F150 and it's quiet on the freeway.

A lot has to do with the rest of the setup, slow exhaust velocity creates resonance I believe.
 

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thats right
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yeah, it would make sense that slow velocity creates the resonance. think about it, resonance is ultra deep, low frequency noise.

thats why i think resonance is helped along by bouncing around in the tailpipe. many after market exhaust companies claim a need to run a resonator when the exhuast pipe gets as long as a ECSB length....
 

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HOT AIR BALLOON OWNER
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Maybe it has something to do with not only cruise RPM but how far your foor is into the pedal to get the truck to move? :think:

Like, my truck requires more pedal at higher speeds obviously despite the RPMs are higher which usually equate to less resonation.

Chrome tips also add to resonation...
 

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Plead The First
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Discussion Starter · #11 ·
Highway does not bother me. It's only when it's under stress at about 1,600 to about 1,900 RPM. I might try just taking off the back section and see how it sounds without it.
 
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