UK Question About Secondary CATS
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Joined: Dec 2014
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C63
UK Question About Secondary CATS
Hi Guys,
In the UK, C63 are not as popular in the US and modifying less so.
Looking at getting a Euro Charger map etc but in the UK, most say there is no point removing the secondary ATS as they make no difference to power, just makes the car louder and there are no dyno runs showing the CATS before and after power gain.
Can you guys comment?
In the UK, C63 are not as popular in the US and modifying less so.
Looking at getting a Euro Charger map etc but in the UK, most say there is no point removing the secondary ATS as they make no difference to power, just makes the car louder and there are no dyno runs showing the CATS before and after power gain.
Can you guys comment?
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C63 AMG
I am probably completely unqualified to answer this but....I think freeing up the airflow at any point through out the exhaust, of course while maintaining the proper back pressure, helps the engine burn more "efficiently".
The more you free up the exhaust, the louder it will get at certain Rpms, but the sound is addicting. I'd be surprised if people who took out secondaries didn't consider at least for a second taking out more (i.e. Headers/resonator/mufflers)
The more you free up the exhaust, the louder it will get at certain Rpms, but the sound is addicting. I'd be surprised if people who took out secondaries didn't consider at least for a second taking out more (i.e. Headers/resonator/mufflers)
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'10 C63
Most people will tell you it frees up a few horses. I can't remember exactly how much but if I recall it should be around 15 hp. Most people do it for the sound. The real power comes from long tube headers, and those will be LOUD.
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Joined: Jun 2012
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From: Edinburgh
C63 - Golf Tdi
I have had my secondary's gutted, it makes the car sound much better, Power? I don't know but I suspect a little more, Whatever you do don't chop out the secondary cats and replace them with straight pipes as you will fail your next mot.
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C63
How much louder are they compaired to with the CATS.
I guess if its no power increase, a normal Eucocharger map is fine and doesnt need re-doing if I take them off later.
I am either going to get some where I can swap them back at MOT time or have the originals gutted out.
I guess if its no power increase, a normal Eucocharger map is fine and doesnt need re-doing if I take them off later.
I am either going to get some where I can swap them back at MOT time or have the originals gutted out.
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Joined: Jun 2013
Posts: 339
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From: UK, London
C63 AMG - PP+
How much louder are they compaired to with the CATS.
I guess if its no power increase, a normal Eucocharger map is fine and doesnt need re-doing if I take them off later.
I am either going to get some where I can swap them back at MOT time or have the originals gutted out.
I guess if its no power increase, a normal Eucocharger map is fine and doesnt need re-doing if I take them off later.
I am either going to get some where I can swap them back at MOT time or have the originals gutted out.
No downside, wasn't looking to add more power, but it pops and crackles more lower down and on the overrun, absolutely no increase in cabin noise inside, no drone, about 3500/4000 Revs far more aggressive sounding
Just had the MOT done and all fine also, so no messing around with swapping back and forth and still have the original pipes if I need to replace and sell the Miltek
Last edited by Dazzagt; Feb 16, 2015 at 09:25 AM.
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From: UK, London
C63 AMG - PP+
http://m.millteksport.com/exhaust.pr...tepreference=2
Secondary cat bypass
Video, although even though I spent ages looking and listening there is nothing like hearing it in real life to be properly sure.
Secondary cat bypass
Video, although even though I spent ages looking and listening there is nothing like hearing it in real life to be properly sure.
