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Author Topic: de-cat  (Read 19992 times)

Offline Janner_Sy

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de-cat
« on: May 14, 2010, 07:41:23 pm »
how much louder would you say a "decat mated to the standard cat back" is over say the stock exhaust system and how loud would it be in comparison to a full TBE.

im going to fiddle with my car again, cos is rubbish now and feels numb and crap when you put your foot down. 

I used to have a 3" pipewerx DP fitted which sounded really meaty and throaty.  I then bolted a piper non res cat back to it, but if anything id say it was then too loud, and my driving slowed down as result of how obvious it was if you stuck your foot down.

So im after some stage 2 perfomrance again but not sure if i should fit a decat for the extra performance or just stick to a downpipe??

Offline owen lcr

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Re: de-cat
« Reply #1 on: May 14, 2010, 07:46:42 pm »
decat gives a small noise increase mate, but nothing compared to a full TBE, if you are after a cheap mod that will give you a little power and noise go for it :happy2:

Offline Janner_Sy

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Re: de-cat
« Reply #2 on: May 14, 2010, 07:52:17 pm »
so its only a small increase.  thats good news. 

what about remaps. Will the remap need adjusting to utilise the decat.  I dont want to fit it and find out that the decat causes loss of power.

BTW I still have all the stage 2 an stage 2+ maps on my STS handset so i can go sraight to stage 2 no issues.

Offline Hurdy

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Re: de-cat
« Reply #3 on: May 14, 2010, 07:54:00 pm »
so its only a small increase.  thats good news. 

what about remaps. Will the remap need adjusting to utilise the decat.  I dont want to fit it and find out that the decat causes loss of power.

BTW I still have all the stage 2 an stage 2+ maps on my STS handset so i can go sraight to stage 2 no issues.

I did back to back dyno's of before and after I had the decat done. The car made 4.5bhp and 4.5lbft extra with the decat and NOTHING else altered. :smiley:
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Offline Tfsi_Mike

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Re: de-cat
« Reply #4 on: May 14, 2010, 07:56:38 pm »
so its only a small increase.  thats good news. 

what about remaps. Will the remap need adjusting to utilise the decat.  I dont want to fit it and find out that the decat causes loss of power.

BTW I still have all the stage 2 an stage 2+ maps on my STS handset so i can go sraight to stage 2 no issues.

I did back to back dyno's of before and after I had the decat done. The car made 4.5bhp and 4.5lbft extra with the decat and NOTHING else altered. :smiley:

John ,

you didnt need to alter ANY revo gubbins?

Was it exhausts Uk behind centertainment?  How much did it cost?  :innocent:

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Offline jon-tfsi

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Re: de-cat
« Reply #5 on: May 14, 2010, 07:59:22 pm »
Decat will help spool up too....

Depends on your software if it will throw a cell of fault code though.

The yanks use a 90 degree wayne angle connector on the lambda sensor to keep it away from the flow of gasses. Loads have done this on the mkv forum and seems to work with stock software as well
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Offline Tfsi_Mike

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Re: de-cat
« Reply #6 on: May 14, 2010, 08:00:49 pm »
Decat will help spool up too....

Depends on your software if it will throw a cell of fault code though.

The yanks use a 90 degree wayne angle connector on the lambda sensor to keep it away from the flow of gasses. Loads have done this on the mkv forum and seems to work with stock software as well

I read stage 2+ software stops the light pinging up :)

Offline jon-tfsi

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Re: de-cat
« Reply #7 on: May 14, 2010, 08:06:57 pm »
The standard downpipe is really restrictive.
After fitting the TBE the gains were great.
After removing it the power loss is really really noticeable !!!

You could just remove the first CAT
This is the major restriction in the standard exhaust as the heat and gasses hit a brick wall exiting the turbo.
Its made from brittle ceramic and can be removed with a little persuasion :smiley:


« Last Edit: May 14, 2010, 08:32:00 pm by jon-tfsi »
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Offline Janner_Sy

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Re: de-cat
« Reply #8 on: May 14, 2010, 08:30:47 pm »
so its only a small increase.  thats good news.  
what about remaps. Will the remap need adjusting to utilise the decat.  I dont want to fit it and find out that the decat causes loss of power.BTW I still have all the stage 2 an stage 2+ maps on my STS handset so i can go sraight to stage 2 no issues.
did back to back dyno's of before and after I had the decat done. The car made 4.5bhp and 4.5lbft extra with the decat and NOTHING else altered. :smiley:

thats good to know.  might order one in a second then.  looking at the options,  

i could order a 2.5" piper Decat downpipe
or a 3" inch decat blueflame.  

Bearing in  mind this is only a k03, what do you think

I read stage 2+ software stops the light pinging up :)
Mike your not allowed any input now :P. Its your fault i want to re mod the car :laugh:

Offline jonnyc

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Re: de-cat
« Reply #9 on: May 14, 2010, 08:35:35 pm »
The standard downpipe is really restrictive.
After fitting the TBE the gains were great.
After removing it the power loss is really really noticeable !!!

You could just remove the first CAT
This is the major restriction in the standard exhaust as the heat and gasses hit a brick wall exiting the turbo.
Its made from brittle ceramic and can be removed with a little persuasion :smiley:




Looks familiar lol..

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Build thread http://www.vagoc.co.uk/vb/showthread.php?t=3128

Offline jon-tfsi

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Re: de-cat
« Reply #10 on: May 14, 2010, 08:40:37 pm »
LOL must be a Gbro thing...

My cat looks much cleaner than yours :P
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Offline jonnyc

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Re: de-cat
« Reply #11 on: May 14, 2010, 08:44:05 pm »
LOL must be a Gbro thing...

My cat looks much cleaner than yours :P

Yeah, G'town massiveeee!..  :grin:

I tried getting it out doing this but failed pretty bad.. Hence the 'singed' look..  :laugh:

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Offline Tfsi_Mike

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Re: de-cat
« Reply #12 on: May 14, 2010, 08:46:49 pm »
The standard downpipe is really restrictive.
After fitting the TBE the gains were great.
After removing it the power loss is really really noticeable !!!

You could just remove the first CAT
This is the major restriction in the standard exhaust as the heat and gasses hit a brick wall exiting the turbo.
Its made from brittle ceramic and can be removed with a little persuasion :smiley:




MOT friendly??  :party:

Offline jon-tfsi

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Re: de-cat
« Reply #13 on: May 14, 2010, 08:47:39 pm »
It passed :booty:
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Offline jon-tfsi

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Re: de-cat
« Reply #14 on: May 14, 2010, 08:49:20 pm »
Lol thats brutal Jonny!!!

A shameless way to treat a new car. :signLOL:

Our resident welder removed the second cat with a little more FINESSE
He cut the cat open with a slitting disc, i removed the guts and he tig welded it back together so well it looks like it was done by machine.....



« Last Edit: May 14, 2010, 09:00:19 pm by jon-tfsi »
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