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2.8 Decat

Discussion in 'Z3 Roadster & Coupé' started by Mole, Apr 25, 2013.

  1. Mole

    Mole Newbie

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    Location:
    Gillingham, Kent
    Model of Z:
    Z3 2.8
    Hello,
    I've been looking around for a decat for the z3 2.8, but have yet to find one.

    Mine was made december 1997, but reg'd in march 1998, so I believe only has a lambda sensor pre-cat.

    If there isn't an 'off the shelf' type product, what about buying a pattern front pipe/cat, and cutting the catalyst out and putting a pipe in its place?

    Any ideas or help would be very much appreciated :)
     
  2. lmrdave

    lmrdave Dedicated Member

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    If you really wanted to get rid of the Cat you will have to cut it out and have a replacement fabricated as it's not straight in and out from memory. If you are intent on doing it I'd weld in a flanged joint and weld flanges on the CAT so it can be replaced for the MOT (or as you say have a complete front pipe spare iwth cat and new one without).
    Personally I would not bother,. you'd be better off replacing the or moding the back box, as I believe the main flow and noise restriction is there.
     
  3. ShoutyRedCar

    ShoutyRedCar Newbie

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    I had exactly that modification done a few years ago. I had the cat cut out and flanged, with a replacement flanged bypass pipe made such that the cat and the bypass can be easily swapped - takes no more than 20 mins to do. This was done at MIJ Performance in Walsall, who also replaced the stock pipe from Ccat back with a stainless mid-sport pipe. The difference in power is immediately noticeable, the engine flows much more freely, and revs with increased power through to the red-line. Worth every penny!!
     
  4. zedonist

    zedonist Guest

    I was going to suggest MIJ Performance, looks like someone beat me to it!! :)
     
  5. Lappintyre

    Lappintyre Regular Member

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    I had my standard cat gutted a few weeks ago as it was shagged, the car is going great since, so much more torque and a beautiful sound too. Mot didn't pick it up either
     
  6. zedonist

    zedonist Guest

    What engine is that on, and do you mean you emptied the cat so it is in place but has no cat material?
     
  7. Lappintyre

    Lappintyre Regular Member

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    Yes that's it, emptied the cat, so the shell is still there. It's a 98 2.8
     
  8. Mole

    Mole Newbie

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    Location:
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    Unfortunately MIJ is a little too far away for me, but I'm hoping to visit a local exhaust place at some point over the weekend. If they won't quote me on doing the decat, then I think I will have to buy the cheap pattern catalytic converter and just remove the cat material like you did Lappintyre.

    If only I had a mig welder!
     

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