De-cat pipe, legalitites and emissions?

Rgm racer

Active Member
Sep 22, 2009
317
0
De-cats and sports cats are both illegal for road use, most sports cats will pass MOT emissions tests a de-cat wont.

Heard that de cats are illegal for road use but first i've ever heard of sports/hi flow cats being so?
 
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Feb 14, 2012
684
0
Slough
"There was a change in manufacturing law for cars made after 2001. Cats have to meet a certain standard if they're sold specifically to be fitted to a post 2001 car. It's basically a way to prevent the cheap cats that fall apart after a year being sold.

Sport cats are almost always sold with a "not for road use" disclaimer"
 

staceys3

K26 S3 8L
Feb 10, 2011
45
0
Maldon, Essex
I just got followed and pulled by traffic police for going a tad over the speed limit

They did mention that I had dipped into 3 figures briefly but they're main concern was whether I had a flamer kit on the car as must have been spitting flames which is a fairly regular occurrence due to set up (small turbo hotside) runs in egt protection fairly regularly

They threatened to get people out and inspect it for a flamer kit or in their words something in my exhaust to ignite fumes, but after repeatedly asking me if I had got something of that nature and me telling them they're welcome to inspect it and saying the cars not running right and a bit rich they let me be with a warning

But not once did they mention a cat or decat to my surprise?
Maybe they're not to bothered and just wanted to try and shake me up or just don't really know to much about cars?....who knows
 

ChrisGTL

'Awesome' LCR225
Nov 17, 2007
2,459
2
Huddersfield
Going through this myself at the moment.

Just spoke to my MOT man and he thinks we are going down the German route of MOT testing (ie, alot more strict and every year unlike German 2 years).

Basically said he is not willing to risk his MOT licence to pass a de-cat I'm thinking of getting, which is completely fair enough - this is his livelyhood at risk!! He said the number of VOSA spot checks is increasing (not sure if this is just scare tactics).

I'm going with the Cell200 sports CAT so I don't need to worry so much about it. I'd love a decat (sound better and cheaper), but really struggling to find a de-cat MOT tester.

Another question then - when it is time to have the MOT would I be best putting the car to standard map with the REVO SPS3 device or leaving it mapped and tweaked?
 

traumapat

Leon Cupra IHI
Jul 24, 2005
5,925
4
sunny sussex
Going through this myself at the moment.

Just spoke to my MOT man and he thinks we are going down the German route of MOT testing (ie, alot more strict and every year unlike German 2 years).

Basically said he is not willing to risk his MOT licence to pass a de-cat I'm thinking of getting, which is completely fair enough - this is his livelyhood at risk!! He said the number of VOSA spot checks is increasing (not sure if this is just scare tactics).

I'm going with the Cell200 sports CAT so I don't need to worry so much about it. I'd love a decat (sound better and cheaper), but really struggling to find a de-cat MOT tester.

Another question then - when it is time to have the MOT would I be best putting the car to standard map with the REVO SPS3 device or leaving it mapped and tweaked?

Providing everythings balanced on the map it shouldnt be a problem. I can turn my map down to around 270bhp but its got through several mots and passes regardless of the power setting. IIRC its a 200 cell.:)
 
Mar 1, 2009
1,079
0
Liverpool
If I remember correctly, the rules have already changed - I think its basically if a car was manufactured with a cat - it must be present and functioning at the time of the MOT.
This is for both petrol and & diesel cars.

I had a 200-cell on my Ibiza Cupra and never had any issues with emissions - although I remember them being borderline.

A friend of mine was pulled over as the police behind him could smell the "rich" exhaust - they told him to have it sorted out but didn't per-sue it (fair play to them) - he then had his exhaust modified so he can swap over the cat for road use, then remove it for track use.
 

staceys3

K26 S3 8L
Feb 10, 2011
45
0
Maldon, Essex

You never been pulled or ever driven behond the speed limit be it 5mph or 50mph?

But on another note its not always brand name sports cats that are considered safe for mot as i had milltek sports cats previously on my car and after 2 years of running they really struggled to get through the mot and just scraped through in the end?
 

staceys3

K26 S3 8L
Feb 10, 2011
45
0
Maldon, Essex
Quite possibly but fueling has been checked with mapping but who knows?

It has had a full rebuild and decat since this occasion so something i'll probably know :)
 
Nov 29, 2009
508
0
Brighouse, W.Yorks
I'm going with the Cell200 sports CAT so I don't need to worry so much about it. I'd love a decat (sound better and cheaper), but really struggling to find a de-cat MOT tester


Your not looking hard enough ;-)

Ny last 3 cars have been decatted and always found a way. Even if it costs a little more some places
 
Feb 14, 2012
684
0
Slough
You never been pulled or ever driven behond the speed limit be it 5mph or 50mph?

But on another note its not always brand name sports cats that are considered safe for mot as i had milltek sports cats previously on my car and after 2 years of running they really struggled to get through the mot and just scraped through in the end?

Yeh i get pulled near enough every week for various "reasons"
I was calling them ******s not you.
 

leoncupra2012

Active Member
Mar 7, 2012
657
5
Cops pulled in the petrol station behind me earlier, (they was going to the shop ) the one in the passenger side got out as i was filling up,'' smells a bit rich '' he says , i replied yeah just the type of car mate, getting checked over in a couple of weeks come payday, to which he replied ' exhaust standard? ' i replied dont know mate was like this when i got it, told me to behave and be safe and got back in the car :rofl:
 
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