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Anyone DeCatted or Sports Cat? Opinions on doing this?

Discussion in 'Z3 Roadster & Coupé' started by [email protected]]{, Sep 9, 2012.

  1. M@r]{

    [email protected]]{ Regular Member

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    Anyone know what gains or losses there are when fitting a decat or sports cat to these cars?
     
  2. HornelZ3M

    HornelZ3M Zorg Addict
    Supporter East Anglian Crew

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    Have a word with Z3cade,( Liam ), hes got a race cat on his M. Still not as fast as mine though ;)
     
  3. z3cade

    z3cade Zorg Guru (III)
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    Any things faster than yours Paul.. It doesn't move out of the garage! :))
     
  4. M@r]{

    [email protected]]{ Regular Member

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  5. HornelZ3M

    HornelZ3M Zorg Addict
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    I`ll let you know i have taken the car out 3 times this week. I did see one z3 coming the other way on my local road, flashed him with my angel eyes and he must have had a problem with his hand cos he only had one finger to wave :-j only joking he gave a nice wave ;)
     
  6. M@r]{

    [email protected]]{ Regular Member

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    If you two aren't going to help me can you take your blossoming bromance onto another thread? :p
     
  7. HornelZ3M

    HornelZ3M Zorg Addict
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  8. z3cade

    z3cade Zorg Guru (III)
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    We're all very close friends on here Mark :-*

    What do you want to know? Surely you'll know that a decat will do?
    Basically it'll free up the exhaust flow and make it a little louder.. Only cons will be having to replace cat for Mot.

    If your making a few changes like induction etc it mite be worth getting it mapped to suit the mods too.
     
  9. hard top

    hard top Zorg Expert (I)
    Dutch Zeds The M44 Massive

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    If its any help, I removed one on a Merc 190E and it improved HP and fuel consumption.
     
  10. zedonist

    zedonist Guest

    It will add to your net BHP as you will have removed the most restrictive element of the vehicle, you will though, as Liam has said need to add an induction kit, free flow exhaust system and get it mapped correctly for the modifications.

    I looked at it for my 1.9, the guys at LongLife said it would add 10 BHP extra to the quoted remap values, which were between 10 and 12 BHP, but it would not pass MOT as there was no CAT, emissions should not be a problem. the other option is therefore a sports CAT which should give you 40% more flow over the standard CAT, again you would need to have mapped to get the best out of it. How accurate the BHP claims are i do not know, but when i come to go for the Sports Cat and Remap i shall get a RR readout before and after.

    I will probably do it next year as i have focused on suspension this year, which is the most worth while modification you can make to the cars, they are fast enough, just need help round the corners and they are a dream, spend the cash on a Bilstein, Eibach and H&R kit first.
     
  11. M@r]{

    [email protected]]{ Regular Member

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    Oh yeah I know what removing will do, but its to what extent. The difference seems to vary quite a lot from car/engine to car/engine. So depending on how much it really does affect the 3.0 M54 will help me decide whether to do it all, get a sports cat or decat completely?

    I've also heard people talk about freeing up the exhaust car reduce low down torque? Something I want to avoid

    Suspension is there for now, just had Spax Coilovers fitted, Powerflex lower wishbone Eccentric bushes (for more caster) and steering rack spacers (for more lock) Then had a full alignment done. As suggested the difference is remarkable!!! I've done this upgrade on many cars and never have I noticed some a difference
     
  12. zedonist

    zedonist Guest

    In all honesty, you will not get more than 10 - 15 HP from this mod, in order to get more you will need to change cams and flow the head and get more air into the car (forced induction). A good head job always paid dividends on fast fords in my day over any other modification (20 30 bhp).

    Freeing up the exhaust should help the torque not decrease it as you have not changed the engine on ly the induction and extraction, you only really tend to lose low down torque on cam changes as you move the power band up and to the right due to valves being open deeper and longer, fast road cams normally start to come in around 3500 rpm and go on to 7500, so you would lose torque lower down with these. to get the best of both worlds you need a VTECH engine but we are not Honda lovers are we ;)

    Ideally you need to identify the rpm range for your sport that the car will be in most of the time and modify to suit, there are a lot of cam options for the six pot, so should be one to suit your sport of drifting
     
  13. M@r]{

    [email protected]]{ Regular Member

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    Some good info there, cheers :-bd

    Where I need the power band is going to become more apparent after Sunday when the car gets its first shake down. But low down torque/power always comes in handy, so I don't really want to go down the cam route and just move the power. In an ideal world I'd like to get a decent exhaust, induction kit and decat, then get it mapped. However I just don't have the budget to do all that in one go right now.
     
  14. peteslag

    peteslag Zorg Legend

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    My advice would be to get the old girl on the track and see how it goes. On my first track day with the Zed I found my 3.0 had the legs to keep up with most other cars in the straights but in the corners the torque and power came too high in the rev range. I find it easier to be smoother if I can hold a higher gear through the corners which is why I got the remap done (150 quid). The power and torque come in much sooner giving the car much more drivability.

    Bare in mind, the remap suits my driving style but it may not necessarily suit yours. Like I said earlier.........see how it goes.........you might even find that you are happy with it as it is. The 3.0 engine is a cracker! :-bd If drifting is your thing then maybe the money would be better put to one side for more tyres. :D
     

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