Aftermarket Exhaust Question..

Hi, I appreciate this has probably been covered somewhere along the line but from searching I haven't yet found a definitive answer so apologies if so!

From what I've read I'm understanding it as people saying cat back systems run from after the secondary cat and require the exhaust to be cut, regardless of if it's resonated / non resonated?
So in order to not have to cut the standard system I would require a decat (then from what I see encounter a flat spot issue..)
So I have two questions..
a) is the flatspot issue still just as prominent with a decat followed by a resonated system?
b) I will attach screenshots from demon tweeks, systems I've been looking at which suggest they run from the primary cat (pre cat on a 197?) and replace the secondary cat.. is this correct or wrong info on their part?
Thanks in advance,

Lee


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Hi Lee,

The standard exhaust has to be cut so you can remove it whether you keep the cat or go decat. Unlike aftermarket exhausts the standard exhaust is in one piece from the diffuser to the pre cat at the manifold so needs cutting to get it out - there is a way of taking it out in one piece but I know it's quite labour intensive if you're having a garage to do it and for what the oem exhaust is worth, it wouldn't be worth it.

A) if you just had a scorpion resonated system and kept the secondary cat in place the flat spot wouldn't be much (if any) worse than standard. The flat spot becomes a lot more prominent when going for non resonated systems and decat, unless you go for the Akrapovic system which removes the secondary cat but doesn't cause a flat spot (mine actually drives better since fitting) but they come with a hefty price tag.

B) Someone will correct me if I'm wrong but Scorpion or Milltek, resonated/non resonated will all run from the secondary cat back, unless of course you opt to fit a decat at the same time.
 
Thank you @matt9566 so if I opt for decat (which I think I probably will for ease of fitment) with resonated its not such an issue as when removing all silencers?!

I did think that was the case with cat back systems running from after the cat However with the website making a clear point of the fact those two systems will replace the secondary cats which threw me and obviously I don't want to order a decat if that section is included and likewise order based on what they are saying to find the information is incorrect.
 
Thank you @matt9566 so if I opt for decat (which I think I probably will for ease of fitment) with resonated its not such an issue as when removing all silencers?!

I did think that was the case with cat back systems running from after the cat However with the website making a clear point of the fact those two systems will replace the secondary cats which threw me and obviously I don't want to order a decat if that section is included and likewise order based on what they are saying to find the information is incorrect.

It won't be as bad as if you went decat and non resonated (which although I've not heard, will be stupidly loud) but you'd still see a more prominent flat spot because you have the decat fitted even with the resonated system. I'm trying to think of someone who has this setup - they might pop up if they read this to say actually how bad it is.

I've tried to show in these pictures to explain better:

The bits circled in red is what you'd receive with the resonated system which will just fit in to the secondary cat. If you order a decat you will receive everything in this photo which will fit in to the pre cat at the manifold.

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This is how the resonated system fits without the decat:

clio-197-cobra-sport-exhaust-fitted-1.jpg


You could always just buy the resonated system, see what you think of it and if you want anymore noise you could add the decat later - It's a pretty simple task to add on.
 
It won't be as bad as if you went decat and non resonated (which although I've not heard, will be stupidly loud) but you'd still see a more prominent flat spot because you have the decat fitted even with the resonated system. I'm trying to think of someone who has this setup - they might pop up if they read this to say actually how bad it is.

I've tried to show in these pictures to explain better:

The bits circled in red is what you'd receive with the resonated system which will just fit in to the secondary cat. If you order a decat you will receive everything in this photo which will fit in to the pre cat at the manifold.

View attachment 112295



This is how the resonated system fits without the decat:

View attachment 112296


You could always just buy the resonated system, see what you think of it and if you want anymore noise you could add the decat later - It's a pretty simple task to add on.

Thanks, that's a lot clearer to see, my initial thought was to try that as you suggested with cat in then go decat if I felt necessary, but after some reading I've seen people say you have to cut the cat and weld the new system to it? I can't see in your pic, but is this how it's done, or can it be sleeved and pasted? It was that which put me off a little and made me think maybe with decat it'd be a more simple swap!
If I haven't already taken the plunge hopefully I'll be able to get an idea by hearing some different set ups at CS Festival!

Thanks again,

Lee
 
Thanks, that's a lot clearer to see, my initial thought was to try that as you suggested with cat in then go decat if I felt necessary, but after some reading I've seen people say you have to cut the cat and weld the new system to it? I can't see in your pic, but is this how it's done, or can it be sleeved and pasted? It was that which put me off a little and made me think maybe with decat it'd be a more simple swap!
If I haven't already taken the plunge hopefully I'll be able to get an idea by hearing some different set ups at CS Festival!

Thanks again,

Lee

From what I can see from the very vague fitting instructions found here at the bottom of the page: https://www.scorpion-exhausts.com/renault-clio-mk3-197-2006-2009-resonated-cat-back-system-imola There is no need to weld anything, you just cut the exhaust 70mm from the lamba and fit it with the clamp/sleeve provided.

It might be worth waiting till CS Festival so you will know exactly what you want after hearing a few different systems, I've known a few people buy systems then not like them.
 
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hi @Shorty197 i know this is an old post but I'm bored at work and just having a read through and wondered what you went for in the end?

I've got the decat with the res scorpion and I am plenty happy with mine.

It's a daily and she pops and bangs every now and again but not enough for it to be annoying or too much in the morning :smile:
 
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hi @Shorty197 i know this is an old post but I'm bored at work and just having a read through and wondered what you went for in the end?

I've got the decat with the res scorpion and I am plenty happy with mine.

It's a daily and she pops and bangs every now and again but not enough for it to be annoying or too much in the morning :smile:
Hey, delayed response from me..
I went for the scorpion resonated in the end, and kept the cat, I'm really happy with it, still pops and burbles on overrun, and sounds pretty awesome when you open it up, but quiet enough to forget it's there when poodling around or sat steady on dual carriageways etc
Think I need to hear one with same system and decat to decide whether it'd be a welcomed upgrade or a bit too much.. getting old now, or feel it at least haha
 
glad you are happy with it...better without the silencer though :french:
It's really quite subtle at the moment until you're really planting it, so I'm tempted to go for the decat seeing as I've still got centre pipe silenced, just need to hear it first to make my mind up as I don't want LOUD, take it you have scorpion with no resonator? Cat or decat?
 
It's really quite subtle at the moment until you're really planting it, so I'm tempted to go for the decat seeing as I've still got centre pipe silenced, just need to hear it first to make my mind up as I don't want LOUD, take it you have scorpion with no resonator? Cat or decat?

Start messing with the cats expect to get issues with flat spots!
 
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I had a resonated scorpion on my 197 and found it to be a really good balance to be fair! It's a cracking exhaust :smile:
Yeah I really do like it, I was just interested in finding out whether a decat would be a welcome improvement or ott, but at the expense of a flat spot and EM lights, I'll stay clear!
 
Yeah I really do like it, I was just interested in finding out whether a decat would be a welcome improvement or ott, but at the expense of a flat spot and EM lights, I'll stay clear!

yea I have decat and as much as i love the sound of it the flat spot is horrendous! havent had it mapped yet so hoping this will help
 
Sorry to bump an old thread but... I see a decat will effect the flat spot. What about is I swapped the standard car for a sports cat? Would this effect the flat spot?