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Effects of putting cat back on? #407734
03/08/2007 16:49
03/08/2007 16:49
Joined: Jan 2006
Posts: 250
Stockton on Tees
aleem Offline OP
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Stockton on Tees
Hiya guys, not posted on the forum much since it went down a wee while ago, and now just getting back into messing around with my coupe wink

My question is, what kind of effect will removing my decat pipe and putting my cat back on have on my driving experience.

The reason I want to put it back on is just to make the exhaust less noisy on motorways. I guess I'll loose some power - 10 BHP-ish? But what about boost characteristics etc?

I'm running around 270 BHP with hybrid turbo, pace intercooler, novitech chip, electronic boost controller.

Cheers,

Al

Re: Effects of putting cat back on? [Re: aleem] #407738
03/08/2007 16:51
03/08/2007 16:51

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The cat will make the car feel as if its struggling more to rise through the revs. Apart from that, no other differences i believe.

Ross

Re: Effects of putting cat back on? [Re: ] #407740
03/08/2007 16:54
03/08/2007 16:54

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You will loose about 3% power I believe (high flow KAT), thats the only real effect. I put my KAT back on because the car stunk without it, it also helps the exhust note when motorway driving! Much better on in my opinion.

Re: Effects of putting cat back on? [Re: ] #407756
03/08/2007 17:22
03/08/2007 17:22
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Posts: 250
Stockton on Tees
aleem Offline OP
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aleem  Offline OP
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Stockton on Tees
I hope it doesn't feel too restricted

Got the day off work so I'm going to get the ratchet set out and swap them around now.

Thanks guys!

Re: Effects of putting cat back on? [Re: aleem] #407757
03/08/2007 17:23
03/08/2007 17:23

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Originally Posted by aleem
I hope it doesn't feel too restricted

Got the day off work so I'm going to get the ratchet set out and swap them around now.

Thanks guys!


Nah. It will just feel restricted to you because you have felt it with it off. You'll know what i mean when you drive it afterwards.

Ross

Re: Effects of putting cat back on? [Re: ] #408180
04/08/2007 03:27
04/08/2007 03:27
Joined: Dec 2005
Posts: 3,694
Midlands
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Mine feels flat as a pancake running with the CAT, very sluggish off the line before the revs build.


1972 Triumph Stag
1984 Alfasud TI
1999 Fiat Coupe Turbo LE
2005 350Z




Re: Effects of putting cat back on? [Re: MCMike] #408219
04/08/2007 04:16
04/08/2007 04:16

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i hated mine when i put the cat back on for the mot, felt sluggish and had loads more lag, couldn't wait to put the decat back on!!

Re: Effects of putting cat back on? [Re: ] #408245
04/08/2007 04:47
04/08/2007 04:47
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Posts: 250
Stockton on Tees
aleem Offline OP
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Well, I put the cat back on and took it for a spin. Agree with everything written above; the power delivery is a little 'strangled' but it is a LOT less noisy.

I no longer have the fighter-jet screem when on full boost, which I know I'm gonna miss laugh but sometimes it was almost unbearable, especially after a long day at work when all I wanted to do was drive quickly and listen to some relaxing music at the same time: impossible combination with the decat wink

How about if I went for a race-cat type thing? How much of the power and noise would I get back?

Re: Effects of putting cat back on? [Re: aleem] #408277
04/08/2007 10:17
04/08/2007 10:17

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What about a decat and a free-flowing silencer? I have a race cat and still is so noisy, so I am going now for a decat and a 65cm long silencer afterwards...

Re: Effects of putting cat back on? [Re: ] #408399
04/08/2007 16:48
04/08/2007 16:48
Joined: Jan 2006
Posts: 250
Stockton on Tees
aleem Offline OP
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aleem  Offline OP
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Sounds like a good idea! Let us know when you have the silencer fitted, and how it feels.

Al

Re: Effects of putting cat back on? [Re: aleem] #408401
04/08/2007 16:50
04/08/2007 16:50

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..Plus my race kat cant flow the 400 bhp I have or so smile

Re: Effects of putting cat back on? [Re: ] #408510
04/08/2007 22:55
04/08/2007 22:55
Joined: Jul 2006
Posts: 1,671
Newport,south wales
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Newport,south wales
Am i right in thinking that decating will improve spool up,
and help acceleration wink

Ben

Re: Effects of putting cat back on? [Re: Benny] #408664
05/08/2007 05:42
05/08/2007 05:42
Joined: Jan 2006
Posts: 250
Stockton on Tees
aleem Offline OP
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aleem  Offline OP
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Yes Ben, having put the cat back on, I can feel the engine being restricted.

The engine was much more free-flowing without the cat, but it was also very loud; fun at times, but gets tiresome for everyday use.


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