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Finally got a new exhaust put together. I assembled a completely new cat-back system with some 2.5in pipe and a Flowmaster HP-2 muffler.
I've got a solid $180 total in it. The system is completely straight, no bends. It stops with a down turn instead of turning 90 degrees toward the driver side and looping around the rear axle.

So far I've gotten quite a few compliments from friends and I love the sound, but the interior resonance is atrocious at 3kRPM. Above that it's non existent and below that it's at least tolerable. But right at 3K it resonates at a note that just hurts. It even gave my sister a headache. I feel like it's got something to do with the exhaust flow at that speed having turbulence or not flowing well. Maybe the stock manifold/cat could be contributing to that?
Suggestions from the experienced exhaust guys?

What's everyone think of the sound?
https://www.youtube.com/watch?v=EzWY-9uMf3o
 

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The sound isn't really my taste. The only vehicles I prefer Flowmasters are those with cammed V8's.

But I do have something constructive to say.

My guess is the amplitudes of the sound waves emitted through the exhaust pipe around 3000 rpm resonate at the natural frequency of one or some of the metal components of your car.

This is merely speculation, however.
 

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Never been a fan of Flowmaster unless it's used on a v8. A resonator might help with the drone you mention ed though. It would be worth looking into since you said it wasn't tolerable.
 

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My Ti is very similar to this i think a ford should be like this, only proper beauce it is part of american muscle class, unless your aim is USDM-styling and sound. Then just buy a yonaka exhaust system great mix between both.

Good Job mate, Love the Flutter with boost that would sound epic mines does the same.
 

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Do a Google search on Side Branch Resonator .
If you have the space to T in another Flowmaster or section of pipe then cap the end that will lesson or eliminate the drone or at least change the rpm in which it occurs. To fine tune it you could adjust the length of pipe and add some sound dampeners just look under a civilian Crown Vic exhaust or a BMW 540 by the rear muffler.
 

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Finally got a new exhaust put together. I assembled a completely new cat-back system with some 2.5in pipe and a Flowmaster HP-2 muffler.
I've got a solid $180 total in it. The system is completely straight, no bends. It stops with a down turn instead of turning 90 degrees toward the driver side and looping around the rear axle.

What's everyone think of the sound?
https://www.youtube.com/watch?v=EzWY-9uMf3o

Not bad at all. I've been looking for exhaust systems that don't have the ricer sound and from what I tell, this has a deeper sound. I'm sure it sounds different in person.

Great job!
 

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Sounds great!! Keep thinking of doin something similar.
 
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