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1.8T downpipe+decat?any good?

Discussion in 'A3/S3 Forum (8L Chassis)' started by sam_20vturbo, Feb 1, 2007.

  1. sam_20vturbo
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    sam_20vturbo Member

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    [Feb 1, 2007]
    #1
  2. Ads

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  3. Prawn
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    Prawn My other car is a MINI!!!!

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    [Feb 1, 2007]
    from what ive picked up about these on this and other forums, if you have an older AGU engine it will work ok, as they only have one lambda i think, the newer DBW engines also have a post cat lambda i think, and will throw up fault codes and some sort of light on the dash.

    as to what gains are available, im not sure, but id be interested to know, as i have seen them too, and would like to know if its worth doing!
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  4. Booth_S4
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    Booth_S4 Riding on V8 power

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    [Feb 1, 2007]
    shame really, would fit an S3 as it has 2 pipes into one at the cat!

    Not really sure whether or not you would see an increase in performance but you will defo notice a big increase in noise!
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  5. sam_20vturbo
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    sam_20vturbo Member

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    [Feb 2, 2007]
    how will i know if i have an older AGU engine? ive got a 1998 1.8t sport...?
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  6. portsA318T
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    portsA318T 'The boat can leave now, tell the crew'

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    [Feb 2, 2007]
    Have a look at the sticker in the engine bay. Thats if it still has it. The engine code should be written on that.
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  7. sam_20vturbo
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    sam_20vturbo Member

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    [Feb 2, 2007]
    but then how will i know once ive got that? sorry im pretty clueless about the whole thing lol

    and also how do i know if mines a facelift model or not? :blush:

    Sam
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  8. portsA318T
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    portsA318T 'The boat can leave now, tell the crew'

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    [Feb 2, 2007]
    I was wrong there. My sticker in the engine bay doesn't say what engine code it is. Sorry. However it was in my logbook. What year is your car and model?
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  9. M44 DUB
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    M44 DUB Member

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    [Feb 2, 2007]
    You'll have a pre-face lift model same as mines
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  10. sam_20vturbo
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    sam_20vturbo Member

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    [Feb 2, 2007]
    its a 1998 A3 1.8 T sport. I think its early 1998 as the cd changer ive just had top buy for it is a pre 1998 fitting.

    Sam
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  11. portsA318T
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    portsA318T 'The boat can leave now, tell the crew'

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    [Feb 2, 2007]
    I have a 98 T Sport as well and its an AGU engine.
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  12. daz2347
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    daz2347 Member

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    [Feb 2, 2007]
    should be a AGU vag changed them mid 2000. pipe works well had one on my old 1.8 gti the only problems is they boom a bit if sitting on the motorway at 60-80 you will soon get peed of with it.
    #11
  13. brucelee1973
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    brucelee1973 New Member

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    [Feb 14, 2007]
    Got a 210 BHP S3 on a 2000 plate, Do you know if this will fit
    #12
  14. Tallpaul
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    Tallpaul Member

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    [Feb 15, 2007]
    No, the one in the link won't fit a K04 turbo or a quattro equiped S3.

    Anyway, you'll fail your MOT without a CAT.

    Also, as mentioned, wide-band lambda equipped cars will throw a fault code and probably mess up the air:fuel ratio unless mapped for the decat.
    #13
  15. Prawn
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    Prawn My other car is a MINI!!!!

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    [Mar 13, 2007]
    sorry to bring up such an old post. but i thought it was far better than starting a new one!

    has anyone actually got any experience with a decatted AGU engine? is the standard cat actually restrictive at all?

    im having my car remapped in a month, the mods when its remapped will be a miltek catback stainless exhaust, CAI, and a forge DV. would it be worth me decating the car as well? i know its an MOT failure, but would the benefits be worth the hasstle of refitting it once a year for MOT? or is it simply a bad idea and not worth it?
    #14
  16. PocketRocket
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    PocketRocket Member

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    [Mar 13, 2007]
    Without cat should help a bit at high revs, but better is to put a 2.5" or 3.0" DP with high flow cat, and avoid pollution:yes:

    What is MOT?
    #15

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