Decat or High Flow Cat?


Wanna kick this topic for a reason. I'm having doubts about buying a JDM Honda cat or sports cat. Cause I've read that the JDM Honda cats (from JDM DC2 en EK9) flow way better than the UKDM/EUDM catalytic converters. Can anyone back this up with number? I have measured the difference on my car (EG5) between stock cat and decat and it costed me almost 1 second in my 0-62mph sprint. So I wanna know for sure.
 
_JT said:
Wanna kick this topic for a reason. I'm having doubts about buying a JDM Honda cat or sports cat. Cause I've read that the JDM Honda cats (from JDM DC2 en EK9) flow way better than the UKDM/EUDM catalytic converters. Can anyone back this up with number? I have measured the difference on my car (EG5) between stock cat and decat and it costed me almost 1 second in my 0-62mph sprint. So I wanna know for sure.
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Correct, the EU/UKDM DC2 Cats are longer (18") & thinner bore than the JDM Cat (12"), They provide more resistance to flow & thus get hotter to work more effectively at passing our stricter emissions laws....

The EU/UKDM Cat is designed to fit a 2" collector so you really need a Cat/Decat to suit your collector size...
 
Only 12"....thats never gonna fit so guess I'm gonna have to get a sports cat :) Thanks.
 
Im running a Tanabe Tuner Medalion decat and without the baffle its dead loud, you cant go above 3krpm without everyone in the local area looking at you (VTEC sounds the shizzle on backlanes however) - personaly im not happy with decat (i like popping and deep idle note) however i hate the deep resonation you get when you let off the gas, not to mention im paranoid to fook all the time so i want a decent sports decat that will pass an mot (having herd lots of storys about the car being more drivable once decatted) any advice on a decent sports decat that dosnt cost the earth! :bow:?

P.S its an B16A2 Civic Coupe.
 
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The simple fact is that decat is illegal on the UK roads, If you are caught running a decat pipe the police can slap you with a £1000 fine. I ask myself is it really worth it ?.
 
Smithy18 said:
The simple fact is that decat is illegal on the UK roads, If you are caught running a decat pipe the police can slap you with a £1000 fine. I ask myself is it really worth it ?.
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I agree I want a high flow cat however the car come without a cat so I would like to know asap which high flow I need for my exhaust I'm a little thick that side of things...
 
offspringy said:
I agree I want a high flow cat however the car come without a cat so I would like to know asap which high flow I need for my exhaust I'm a little thick that side of things...
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i have no idear about cats really, someone will be able to help
 
So whats the opinion on this now. Did anyone get a Magnaflo High Flow cat. I am thinking about one of these for mine.
 
You can buy Magnaflow universal ones mate. However, you would need to get the flanges welded on the end of the high flow cat and possibly some adjust to your b pipe.

I don't know if I can be arsed with all the hassle. May just but a standard cat back on!
 
Yup I found a supplier not too far away. I will call on Monday and get some prices for the Cat and fitting. Then we can see what we are looking at cost wise.
 
I have had to refit a stock cat to my Tanabe SMR this month and it sounds bloody awful. Now sounds like every other chavved up Civic with an eBay special universal back box with the horrible high pitched whistle which it never had with the decat.

Screw emissions, screw being legal, screw the police. Decat FTW. :nice:
 
McJazz said:
Yup I found a supplier not too far away. I will call on Monday and get some prices for the Cat and fitting. Then we can see what we are looking at cost wise.
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Universal one?
 
de cat: who cares about planet 2012 it will be destroyed anyway !! lol !
hi flow's are better any way ....
 
It depens on what you want i have had both and there is good and bad points to both. Go de-cat for noise and power or flow cat for enviroment and less performance.
I would go de-cat sounds so much better but each to there own.
 
Decat - Best flow but from tests done only 1hp over a high flow cat. Won't pass emissions, need to change come MOT time.

Hi flow - Only 1hp loss over a decat, will pass emissions (depending on the hi flow). Direct fit hi flows are expensive, universal ones need flanges welding a long with possible adjustments to the b-pipe.

OEM cat - Passes emissions, worse flow but no bad as JDM cat's are better than UKDM cat's I've read?

The question is for me, how much gains in torque/hp will be found with a hi flow cat over a JDM OEM cat? The hassle of getting flanges cut etc has to be worth it for me or I am just going to leave my cat on.
 
I am looking at the Magnafow High Flow cat as it was recommended to me by a member over on the DC2 forum who races his teg and its only £80 plus the flanges and fitting. Also as I want to use the car for competition in 2010 you must have a cat fitted.
 
McJazz said:
I am looking at the Magnafow High Flow cat as it was recommended to me by a member over on the DC2 forum who races his teg and its only £80 plus the flanges and fitting. Also as I want to use the car for competition in 2010 you must have a cat fitted.
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Where you getting flanges from?
 
ive got a mate who does my mot and passes me for the cat lol, but i will be changing to a high flow cat in the future just for the hassle free
 
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