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Hey guys,

I've got a full custom 3.5" exhaust coming from my precision turbo into a 3.5" decat pipe, into a 3.5" oval mid muffler and exiting through a 3.5" inlet and 4.5" tip cannon..

Now after putting cams in and a bigger single turbo the exhaust note has gotten louder,

I want to get rid of the rear cannon and was thinking of afew options

If anyone can advise which would be best to quieten it down please let me know

So far I looking into a Vibrant street oval muffler which is 3.5" in and out (and painted black which I like)

http://vibrantperformance.com/catalog/index.php?cPath=1022_1031_1109

Or considered running a hooker aerochamber, again 3.5" in and out, I can paint it black as I'm not a fan of shiny stainless exhausts

http://www.ebay.com.au/bhp/hooker-muffler

Would any of these be worthwhile to replace my cannon with?

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Of the 2 choices the Vibrant. 304 stainless steel designed for noise reduction - plus looks better.

(have a mint 5zigen Jasma oval Muffler in black but alas it's 3" Michael)

What about places like HiTech in Sydney?

The Vibrant is 304 Staineless steel Painted black already :yes:

http://vibrantperformance.com/catalog/product_info.php?cPath=1022_1031_1109&products_id=1158&osCsid=99046d0a9d204006429f0988a5c39be2

Still requires modification to fit and flange :(

Edited by Sinista32

http://www.activeexhaustsystems.com.au/index.php?option=com_content&view=article&id=74&Itemid=216

I have one of these. I went from 2 hooker mufflers to one of these and it's 20db quieter and flows better

Two of the same muffler doesn't ever really work well as different designs cancel out certain frequencies so two of the same won't be much quieter at all.

I have an aero chamber and a straight through resonator and it is below legal volume.

Spoken to active exhaust systems, and there knowledge and products are far superior to the rest

Plus they just down in Wollongong so keep the money in Australia and support a small Aussie business

Win win

Ps look up "active exhaust systems" on Facebook they got some tasty pics !

Two of the same muffler doesn't ever really work well as different designs cancel out certain frequencies so two of the same won't be much quieter at all.

I have an aero chamber and a straight through resonator and it is below legal volume.

Not quite right there mate,it comes down to the distance from the exhaust port to the muffler.For example if you only run say a rear resinator then at certain revs you will get that annoying drone sound as you are missing some frequencies with only having the rear one.Then go mount the same resinator/muffler in the middle of the system as well then this will help cancel out frequencies the rear one is missing.I know this is slightly of topic but with V8s N/A they quite often run small front resinators,a middle muffler and twin rear resinators,this will be about as good as it gets.The bonus with a turbo car is the turbo actually works as a noise suppressor,therefore less mufflers are normally needed to gain the same decibal reading.Of course screamer pipes change everything,lol

The bonus with a turbo car is the turbo actually works as a noise suppressor,therefore less mufflers are normally needed to gain the same decibal reading.Of course screamer pipes change everything,lol

The one hassle with the "turbo as muffler" idea, true as it is, is that in order to get the most power out of the turbo you tend to want the biggest diameter pipework after it, which then works against silencing the noise.

The one hassle with the "turbo as muffler" idea, true as it is, is that in order to get the most power out of the turbo you tend to want the biggest diameter pipework after it, which then works against silencing the noise.

Correct,thats why you want the biggest and longest ones you can fit

I manufacture AES mufflers. To make a good straight through (absorbtion) muffler you have to tick all the boxes. The perforated tube must have the correct open area ( holes /sq in. and between 3 and 3.5 mm) I wrap the perforated tube with INOX which is capable of high temps and then pack the muffler AT THE CORRECT DENSITY with either quality stranded fibreglass or GTB depending on the application. If it is a circuit racer then packed entirely with INOX. I also install an expansion joint in the perforated tube to prevent fatigue. This makes it possible , with some effort to repack the muffler if ever required giving it a second life. The biggest killer of mufflers is carbon resulting from a bad tune, too rich. These mufflers were developed on rotaries which provide the worst possible enviroment for a muffler i.e. very noisy and hot. They have a deeper , quieter sound. I am continueing r&d constantly to improve. It is all about silent high flow.

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