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Discussion Starter #1
Just wondering if anyone can shed any light on the subject and are there advantages to either one of them? I need to get some silencing in my exhaust. Too loud for me!

Cheers
 

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the difference is internal design. In silencer the gases enter with one tube that changes from solid to perforated into a chamber inside silencer filled with glass fibre or steel wool. Gases expand freely into the volume of the chamber. Than the gases may be passing through more chambers and various internal pipes and finally are picked up by and exit pipe. Resonator is a straight pipe that has a perforated section that passes through a box filled with damping material. As the gases have some chance to expand through the holes they change their speed and frequency so they "quieten" the sound.

silencer:
http://www.max-boost.co.uk/max-boost/images/LET/silencer-highflow.jpg

resonator:
http://1.1.1.1/bmi/images.off-roadweb.com/tech/0705or_03_z+banks_power_jeep_exhaust+muffler_cutaway.jpg
http://t2.gstatic.com/images?q=tbn:ANd9GcTLAEXdLfRVmjDm_zScz6X7fnQwOsUyx-esAa4xOmsOut1ij7k9

silencer - quieter, more options to tune sound thanks to internal chambers, volumes, pipe lenghts (as BOSE subwoofers) but more expensive to make and restricts flow more than resonator

resonator - free flowing, close to straight pipe performance but not so quiet and very difficult to tune its sound, basically only by changing perforation size and structure.
 

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Discussion Starter #3
Straight forward then! Ha. Cheers for the info. Does one have a slight performance loss/gain over the other? I've got a ragga cat bk non resonated with the gtv manifolds/eq. Too loud for me. Which of the above would you recommend? Just to generally quieten it down and maybe attempt to take some of the boomyness away although I realise this is down to the ragga exhaust..

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Gotcha your second link doesn't work (server busy)
 

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I'd recommend changing the backbox for a silenced one. You're not going to find anywhere in the rest of the exhaust system to put a big enough silencer in unfortunately.

A standard GTA exhaust sounds lovely with decat manifolds and equal length front pipes and is perfectly civilised.
 

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probably your only option is to get ragga or other center silencer. GTV + EQ are usually quite loud if you have backbox only. My opinion is that for daily use a central silencer is a must.
 

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Gotcha your second link doesn't work (server busy)
I am on some weird PC and it keeps reloading every page 20 times... Well, just put "exhaust resonator design" in google pictures and you will find something :)
 

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A standard GTA exhaust sounds lovely with decat manifolds and equal length front pipes and is perfectly civilised.
That´s a very good advice as well. Backbox doesn't affect performance much anyway. So keep the performance oriented parts close to engine and standard backbox at the end... If only the standard backboxes wouldn't rust so much after the first rain...
 

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A standard GTA exhaust sounds lovely with decat manifolds and equal length front pipes and is perfectly civilised.
yep thats what i got. There is a vid of it somewhere.
Lemi
 

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For the moment, I have decat manifolds + FP EL + standard main cat + silenced pipe (scorpion) and OEM back box
It's a good combo, not too loud but more than full stock exhaust. I painted the OEM backbox in black paint (high T° of course and for the moment, it's ok). By this way, it will probably protect it from quick rust and it is less visible in black
 

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Discussion Starter #12
Lemi I listened to you videos, yours sounds great. Mine didnt sound like yours unfortunately. Mine just sounded really raspy and tinny. Yours doesnt sound like that from memory does it? Quite a sweet high pitched sound?
 

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Mine used to be tinny and raspy when I had stainless steel equal length pipes, but I changed for mild steel and it sounds much much better. We don't have an issue with rust here though...
 

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Discussion Starter #14
Yeah I thought it might of been that. I can't stand that tinny noise. Yours sounds great. Would of left the standard cat bk on if it of sounded like that. Pud do you do the eq lengths in mild steel?
 
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