What's cat back?

1. JPS93 Infrequent Poster Joined: Apr 2014 Huddersfield Posts: 236 Citroen Saxo VTR 53

   #1 6th April 2014, 20:02

   Looking for an exhaust and see this term cat back a lot! Am not very good with cars but wanting to get into it as I love them! Been looking for a saxsport exhaust and they say decat too I know that's the catalytic converter taken out. If I get a decat exhaust what do I do when it comes to mot? And will it pop and that? Cos I'm not really a bit fan of that. Cheers lads!
   
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2. Jigs2895 Established Member Joined: Jan 2013 Portsmouth Posts: 1335 1997 Mk1 VTS

   #2 6th April 2014, 20:16

   A cat back means the exhaust goes to the cat, and back.
   
   If you have a MK2 then your cat is in your manifold, so you can fit a catback and still pass an MOT however you won't get any pops and bangs.
   
   If you fit an aftermarket manifold along with a saxsport then you will but your have to fit your cat back to your car for MOT time.
3. JPS93 Infrequent Poster Joined: Apr 2014 Huddersfield Posts: 236 Citroen Saxo VTR 53

   #3 6th April 2014, 20:18

   Which bits the cat then? Is there any guides or pics on the forums about?
   
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4. Jigs2895 Established Member Joined: Jan 2013 Portsmouth Posts: 1335 1997 Mk1 VTS

   #4 6th April 2014, 20:22

   A catalytic converter simply cleans up the exhaust fumes to make it more environmentally friendly, but with that it also restricts the flow of the gasses, slowing performance, which is why people 'de-cat' their cars.
   
   In MK2's the cat is just after the manifold and is round. In MK1's they are underneath the car and part of the centre pipe. If you use the search button your find out everything you need to know, there is loads of threads on stuff like this.
5. JPS93 Infrequent Poster Joined: Apr 2014 Huddersfield Posts: 236 Citroen Saxo VTR 53

   #5 6th April 2014, 20:27

   Ahh right yeah I watched a video online cheers mate! Why do they call it a decat exhuast though if the catalytic converter is on is it because it's been designed for being used for a car with no catalytic converter?
   
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6. Pricklep Saxperience Hardcore! Joined: Mar 2008 Posts: 31279 Citroen Saxo VTS, S60 D5

   #6 6th April 2014, 20:28

   Takes the silencer out.
   
   Same difference wheter the cat is in the mani or underneath. VTR or S?
7. Jigs2895 Established Member Joined: Jan 2013 Portsmouth Posts: 1335 1997 Mk1 VTS

   #7 6th April 2014, 20:30

   The saxsport is actually called a 'dummy cat' because in the centre pipe it has a fake cat, i'm not entirely sure why, I guess to fool the police or something.
   
   Obviously if you fit a saxsport to a MK1 then you are 'de-catting' it because the cat is in the centre pipe for MK1's.
8. Pricklep Saxperience Hardcore! Joined: Mar 2008 Posts: 31279 Citroen Saxo VTS, S60 D5

   #8 6th April 2014, 20:33

   Cats underneath on mk1 and 2 vts so a saxsport would decat them. Not entirly sure on vtrs, but im sure a saxsport wouldnt decat a mk2 vtr as the cats in the mani.
9. Quick Saxperience Post Whore Joined: Mar 2003 United Kingdom (England) Posts: 7064

   #9 6th April 2014, 20:37

   Often a dummy cat works with flow & pulses from the engine.
10. JPS93 Infrequent Poster Joined: Apr 2014 Huddersfield Posts: 236 Citroen Saxo VTR 53

    #10 6th April 2014, 20:39

    Mani? Got a vtr mate mk 2! Want a fresh exhuast on but don't have a clue really don't want a decat one anyways just summat that's sound sweet! Any recommendations?
    
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11. Pricklep Saxperience Hardcore! Joined: Mar 2008 Posts: 31279 Citroen Saxo VTS, S60 D5

    #11 6th April 2014, 20:40

    You'll need a mk1 vtr manifold/downpipe or a 421 to decat it.
12. Mickswan Saxperience Forum Bum Joined: Apr 2013 Jarrow Posts: 4022 2003 Icelandic Grey 16v VTR 1991 Daihatsu GTti

    #12 6th April 2014, 20:50

    Here's a pic of my standard mk2 manifold which I dropped of my car today. As you can see the large cylinder with the heat shield is the cat.
    
    
    
    By removing this and putting a new manifold on it's now de-cat. When I had this on it was cat back.
13. Mickswan Saxperience Forum Bum Joined: Apr 2013 Jarrow Posts: 4022 2003 Icelandic Grey 16v VTR 1991 Daihatsu GTti

    #13 6th April 2014, 20:52

    If your not too clued up I'd go for a piper or something which doesn't need the oil filter to be relocated.
    
    Keep an eye on the for sale section.