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Power loss from exhaust mods? #1509665
28/09/2014 19:22
28/09/2014 19:22

D
Downhillryder
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Downhillryder
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I have a 2.75 inch exhaust system all the way from turbo to tip. It consists of center box and back box but no cat. The pipe is continuous from downpipe through the center box, over the wheels to just before the start of the back box where there is a flange join. The car has been tested to 315bhp, but that was a while ago and before my ownership.


I'd like to get legal and would like to add a sports cat without loosing power. Since 2.75 inch parts are hard to find on ebay/Web I'm considering the following :

Cut out center box, replace with 2.75"/3" expander connected to a 3", 200 cell sports cat connected to a small center box with 3" pipe fittings connected to 3"/2.75" reducer back into main pipe.

Can anyone give me a guess as to how much power this might cost?

Is there better way to add a cat?

Should I just get a complete spare system for mot time?

Just trying some forward planning for once!



Re: Power loss from exhaust mods? [Re: ] #1509684
28/09/2014 23:18
28/09/2014 23:18
Joined: Jan 2010
Posts: 2,614
Bucks
jame5 Offline
I need some sleep
jame5  Offline
I need some sleep

Joined: Jan 2010
Posts: 2,614
Bucks
Top gear in st.albans fitted a 100 cell race cat on my powerflow system witch I think was 2.75, may be worth finding your local powerflow dealer.


Re: Power loss from exhaust mods? [Re: ] #1509691
28/09/2014 23:57
28/09/2014 23:57
Joined: Nov 2006
Posts: 1,580
Melbourne, Australia
Scuderia Offline
My life on the forum
Scuderia  Offline
My life on the forum

Joined: Nov 2006
Posts: 1,580
Melbourne, Australia
Probably no power loss.

Re: Power loss from exhaust mods? [Re: ] #1509702
29/09/2014 09:02
29/09/2014 09:02

M
mr_cheese
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mr_cheese
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M



Jst do wat most of us do and keep a cat for mot time, only takes couple min to swap over!

Last edited by mr_cheese; 29/09/2014 09:03.
Re: Power loss from exhaust mods? [Re: Scuderia] #1509703
29/09/2014 09:07
29/09/2014 09:07

M
mr_cheese
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mr_cheese
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M



Originally Posted by Scuderia
Probably no power loss.


No power loss frm putting cat back on??
Sure as hell does!! Without cat my wheels spin at full chat yet doesnt when cats on!! Not very.sicentific like but does show how much power you loose without that freeflowing air!

Re: Power loss from exhaust mods? [Re: ] #1509740
29/09/2014 14:04
29/09/2014 14:04
Joined: Nov 2006
Posts: 1,580
Melbourne, Australia
Scuderia Offline
My life on the forum
Scuderia  Offline
My life on the forum

Joined: Nov 2006
Posts: 1,580
Melbourne, Australia
Originally Posted by mr_cheese
Originally Posted by Scuderia
Probably no power loss.


No power loss frm putting cat back on??
Sure as hell does!! Without cat my wheels spin at full chat yet doesnt when cats on!! Not very.sicentific like but does show how much power you loose without that freeflowing air!


Is that a 3" Hi flow cat or the std one?

Re: Power loss from exhaust mods? [Re: ] #1509743
29/09/2014 14:49
29/09/2014 14:49
Joined: Aug 2008
Posts: 439
gillan Offline
Enjoying the ride
gillan  Offline
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Joined: Aug 2008
Posts: 439
i never lost any power with a sports cat on well nothing noticeable anyway.

Re: Power loss from exhaust mods? [Re: ] #1509816
29/09/2014 22:11
29/09/2014 22:11
Joined: Aug 2006
Posts: 707
TurboNick Offline
Enjoying the ride
TurboNick  Offline
Enjoying the ride

Joined: Aug 2006
Posts: 707
I doubt you will lose any power. Also being a fiat owner we go to mechanics so many time we get to know the guys there n they pass your car anyway.

Well they do mine anyway never once even had a car on my car apart from its birth.


Re: Power loss from exhaust mods? [Re: Scuderia] #1510090
02/10/2014 01:50
02/10/2014 01:50

M
mr_cheese
Unregistered
mr_cheese
Unregistered
M



Originally Posted by Scuderia
Originally Posted by mr_cheese
Originally Posted by Scuderia
Probably no power loss.


No power loss frm putting cat back on??
Sure as hell does!! Without cat my wheels spin at full chat yet doesnt when cats on!! Not very.sicentific like but does show how much power you loose without that freeflowing air!


Is that a 3" Hi flow cat or the std one?


Not sure if its high flow but yea its 3inc cat, got full 3inc exhaust system
you see.. but even tho its 3inc cat it deffo drops performance when put bk on for mot..
As i said befor without cat i floor the loud peddle and my wheels spin but soon as cats on for mot she wont spin at full chat!! Make your own minds up! Lol


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