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Old 12-09-2008, 12:55 PM   #1
watchunglava
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Default best resonator

At this point I don't even care about flow. I need the best performing exhaust around as far as muffling is concerned. The exhaust pulses and valve noise resonating through my system which tottally has a vibrant ultra quiet resonator and an oem wrx muffler, are so ugly I need something that will handle those noises.

From what I've read the higher pitched sounds are the harder ones to control.

I like the job the mufflers doing but I need something upstream to grab the valve noise before it has a chance to resonate.

I'm not against using a full chamberd muffler in place of a resonator.

So who makes the best silencer around?
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Old 12-09-2008, 02:38 PM   #2
Bluefoton
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Is it still from the exhaust noise? Or rather the noise coming from the engine itself as well as the headers? The engine on the impreza has rather poor sound insulation (blame partially the boxer design for that...)
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Old 12-09-2008, 03:12 PM   #3
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well no its not really the exhaust noise , that was muffled and now sounds puffy instead of drony by the oem wrx muffler. but the rattle like little nomes in the pipes hammering away with ball peen hammers its horrible. its most likely valve train noise and its being amplified by the headers at certain frequencies.

i love the power my headers give me , but i need to do something about that chainlink fence crashing into an aluminum barn sound .
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Old 12-09-2008, 10:47 PM   #4
Eyedoc Orlando
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I think aftermarket wise the quietest is the new one from Borla for the 2.5i
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Old 12-10-2008, 05:21 PM   #5
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I have OBX headers & a high-flow cat, plus a custom 2 1/4" catback exhaust, and I, too was plagued by the tinny rattling between 2500 and 3000 rpms after installing the headers. The most effective fix for me was actually installing cams. The change in cam profile completely changed the exhaust note, cutting back on the buzzing in mid-rpm's. It's still not perfect, but better than it was.
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Old 12-10-2008, 06:32 PM   #6
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That's not what I wanted to hear

Did you ever try resonators?
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Old 12-10-2008, 06:51 PM   #7
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I just use a resonator from Magnaflow. I think it was a foot in length.
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Old 12-10-2008, 07:19 PM   #8
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Er, unless i'm missing something - what's wrong with the stock exhaust?

You know it's tuned pretty carefully to work well with the motor, right?



What problem are you attempting to solve with a different exhaust?
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Old 12-10-2008, 07:33 PM   #9
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i've had good results with presilencers from racingbeat.com, which is essentially a glass pack without the 'glass. it's stainless construction and beautifully made, packed with stainless steel wool. rotaries are notorious for metallic, tinny exhaust noises and ridiculously high exhaust temps, so if it can handle an rx-7's glass pack melting exhaust, it should handle the wrx's. linked below (site is in frames, so it may come out weird)

http://racingbeat.com/resultset.asp?PartNumber=16403
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Old 12-10-2008, 08:05 PM   #10
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Quote:
Originally Posted by sniper1rfa View Post
Er, unless i'm missing something - what's wrong with the stock exhaust?

You know it's tuned pretty carefully to work well with the motor, right?



What problem are you attempting to solve with a different exhaust?
We all want more power.
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Old 12-10-2008, 08:43 PM   #11
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Yeah, but you aren't going to find more power without being louder.

Guarantee an aftermarket exhaust with a bunch of crap to quiet it won't be any better than the stocker.
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Old 12-10-2008, 08:49 PM   #12
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how much you wanna put behind that statement sniper?
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Old 12-10-2008, 08:53 PM   #13
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goddamn just talked to pat olsen over pm from a 10 hour shore leave he had . he filled me in on what he thinks. and im inclined to agree with him.

but sniper omg dude you dont even realize how awesome my set up feels and how close i am to sounding pretty stock. i would seriously burn your wagon . so whatever maybe i think g/rev is gallons . lick my balls !!!!
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Old 12-10-2008, 08:53 PM   #14
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quite a bit. Betcha subaru didn't just slap some pipes on and call it a day. That's not how engineering works.


Unless, of course, you want to show me quite a bit of math and flow calculations/simulations for your new setup.
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Old 12-10-2008, 08:54 PM   #15
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ill show ya whatever ya want. as soon as i can present my car in public !!!!!! hahahahaha it sounds like ****!
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Old 12-10-2008, 09:03 PM   #16
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i will say this the stock exhaust works evenly through the whole rpm range! but defiatly is not designed for maximum flow velocity. im not concerned with the loudness anymore its fixed. the problem is this insane rattle !!!!!! most likely being caused because the obx's are the cheapest pieces of pipe ever made
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Old 12-10-2008, 09:03 PM   #17
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Quote:
Originally Posted by watchunglava View Post
goddamn just talked to pat olsen over pm from a 10 hour shore leave he had . he filled me in on what he thinks. and im inclined to agree with him.
What did you guys talk about?
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Old 12-10-2008, 09:17 PM   #18
watchunglava
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he hasnt had a problem with either of his set ups but thinks mine might have been made with thinner pipe walls
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Old 12-10-2008, 09:25 PM   #19
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Have you tried shoving something between the pipes yet? Header wrap, or some really packed in fibreglass insulation, etc. Like I said, I don't think that's it, but it would be a quick and easy test.

The dude's comment about changing cams changing the sound really points the finger at it being valve noise.
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Old 12-10-2008, 09:26 PM   #20
watchunglava
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man i havent it snowed yesterday and rain today im waiting to get under there so bad . that will be the first thing i do is check all the heat shields and look for some sort of contact somewhere
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Old 12-10-2008, 09:49 PM   #21
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What is making the noise?!

Metal on metal vibration?!

Feel like maybe fixing it with something?


I guess I don't know what you're whining about.

Anything banging against the chassis? The header pipes banging together at the collector? A hanger hook rattling against something that isn't rubber? Is it just a pipe resonating that you could probably quite easily restrict with some header wrap? one more for good measure
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Old 12-10-2008, 09:54 PM   #22
watchunglava
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Old 12-10-2008, 10:01 PM   #23
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That definitely sounds like some sort of metal on metal contact.
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Old 12-10-2008, 10:15 PM   #24
watchunglava
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yea that isnt my car .but thats the sound . it can be worse at times too. sometimes its present and other times under the same conditions it is not
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Old 12-10-2008, 10:20 PM   #25
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Quote:
Originally Posted by Back Road Runner View Post
What is making the noise?!

Metal on metal vibration?!

Feel like maybe fixing it with something?


I guess I don't know what you're whining about.

Anything banging against the chassis? The header pipes banging together at the collector? A hanger hook rattling against something that isn't rubber? Is it just a pipe resonating that you could probably quite easily restrict with some header wrap? one more for good measure
We don't know what's making the noise, that's the problem. I've been through everything you list and it's none of those things. I don't think anyone who has the OBXes and has the rattle has ever come up with a definitive answer, sadly.
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