Make a donation

Author Topic: cheap pre de-cat  (Read 3322 times)

Offline Jeffchiz

  • Always Involved
  • ****
  • Thank You
  • -Given: 13
  • -Receive: 2
  • Posts: 123
    • Email
cheap pre de-cat
« on: August 25, 2014, 06:34:48 pm »
Hi all, will be having a remap done soon but i keep thinking about going a little bit further, as we all know the pre cat is very restrictive, and i dont want an expensive miltek or do a bodge job and smash the cat up, so i saw this downpipe and de-cat pipe on ebay its cheap but surely its gotta be better than just smashing the pre-cat up?

I would also sell on the de-cat pipe as  would only want the precat removing, does that sound right?? Also this with a new intake would be enough for a stage 2 map? Or surely without adding a 'label' to the map it'll just be a map to suit my car and mods surely?
http://www.ebay.co.uk/itm/AUD-A3-VW-GOLF-2-0T-TURBO-3-STAINLESS-STEEL-EXHAUST-DECAT-DOWNPIPE-DE-CAT-/380861796775?pt=UK_CarsParts_Vehicles_CarParts_SM&fits=Model%3AGolf|Plat_Gen%3AMK+V&hash=item58ad21d1a7

Offline v4rley

  • Just look at my post count
  • ******
  • Thank You
  • -Given: 29
  • -Receive: 104
  • Posts: 1026
Re: cheap pre de-cat
« Reply #1 on: August 25, 2014, 07:30:16 pm »
Have looked at them downpipes too. Obviously de-cat would require being coded out. Not sure you would be able to just use the new stainless downpipe, as the stock downpipe and cat is one section with no joints so some how you would have to cut and 'bodge' the two together. Think I'm going to try removing the pre-cat, several on here have done so and seems a good place to start.

Offline Jeffchiz

  • Always Involved
  • ****
  • Thank You
  • -Given: 13
  • -Receive: 2
  • Posts: 123
    • Email
Re: cheap pre de-cat
« Reply #2 on: August 25, 2014, 09:05:16 pm »
ah right i assumed the downpipe was separate to the cat, i have a mate with the new version of vag com so that shouldnt be an issue coding it i just cba with changing the cat over at mot time, so i assume the best thing to do is look for a cheap sports cat with no pre cat or as you say butcher the oem cat with this aftermarket downpipe but that will take the cheapness out of it which is the only thing that is swaying me towards a stage 2 map as i have another project which is my toy this is just supposed to be a sensible daily car so i dont need to go all out on it

if i am going to get the new downpipe welded to the oem cat i might aswell just not buy the downpipe and just go straight to a custom exhaust centre and get them to fab one up, while im there they can do the suitcase delete and get some r32 pipes welded on :D

Offline banksy21

  • Always Involved
  • ****
  • Thank You
  • -Given: 0
  • -Receive: 4
  • Posts: 85
    • Email
Re: cheap pre de-cat
« Reply #3 on: August 27, 2014, 04:31:21 pm »
ive got one of those cheap ebay downpipes fitted, perfect fit and when i de catted mine i didn't even get a light on the dash.

Offline GTI-Ross

  • Just look at my post count
  • ******
  • Thank You
  • -Given: 5
  • -Receive: 26
  • Posts: 1057
  • Learning All The Time :)
    • Email
Re: cheap pre de-cat
« Reply #4 on: August 27, 2014, 05:32:26 pm »
ive got one of those cheap ebay downpipes fitted, perfect fit and when i de catted mine i didn't even get a light on the dash.

^^^^What are the welds like on them & what grade stainless steal is it?
MK6 GTI CSG | Revo Stage 2 | Revo Stage 2 Intake | VWR SubFrame Mount | VibraTechnics Upper Engine Mount | VibraTechnic Transmission Mount | SuperPro Anti Lift Kit | H&R ARB's | Bilstein B12 | TT Short Shifter |Mintex M1144 Race Pads | HEL Braided Lines |

MK5 GTI - DSG + Extras (Sold because DSG was Soooo Boring !!!)


Offline GrayMK5GTI

  • Global Moderator
  • Just look at my post count
  • *
  • Thank You
  • -Given: 125
  • -Receive: 248
  • Posts: 4165
Re: cheap pre de-cat
« Reply #5 on: August 27, 2014, 05:40:00 pm »
ive got one of those cheap ebay downpipes fitted, perfect fit and when i de catted mine i didn't even get a light on the dash.

^^^^What are the welds like on them & what grade stainless steal is it?

Most of the eBay downpipes look very well made. Even if a weld fails, it's then on par with a Milltek  :signLOL:
NOW: 2015 Golf R DSG 5 Door, Lapiz Blue, 19s, Discover Nav, Reversing Camera
GONE:2007 Black GTI Edition 30 3dr

Offline banksy21

  • Always Involved
  • ****
  • Thank You
  • -Given: 0
  • -Receive: 4
  • Posts: 85
    • Email
Re: cheap pre de-cat
« Reply #6 on: August 27, 2014, 06:16:20 pm »
ive got one of those cheap ebay downpipes fitted, perfect fit and when i de catted mine i didn't even get a light on the dash.

^^^^What are the welds like on them & what grade stainless steal is it?

the fit is excellent, welds are excellent and sorry don't know what grade steel it is. Im running stage 2+ in my Cupra 357bhp and its held up fine so far with no cracking
anything better than milltek haha

Offline GTI-Ross

  • Just look at my post count
  • ******
  • Thank You
  • -Given: 5
  • -Receive: 26
  • Posts: 1057
  • Learning All The Time :)
    • Email
Re: cheap pre de-cat
« Reply #7 on: August 27, 2014, 07:35:01 pm »
ive got one of those cheap ebay downpipes fitted, perfect fit and when i de catted mine i didn't even get a light on the dash.

^^^^What are the welds like on them & what grade stainless steal is it?

the fit is excellent, welds are excellent and sorry don't know what grade steel it is. Im running stage 2+ in my Cupra 357bhp and its held up fine so far with no cracking
anything better than milltek haha


Ha ha this is true.

What size does it reduce to? I have a 3" Milltek Race catback and wonder if it will to that or does it fir to the OEM 2.37" pipe. Thanks
MK6 GTI CSG | Revo Stage 2 | Revo Stage 2 Intake | VWR SubFrame Mount | VibraTechnics Upper Engine Mount | VibraTechnic Transmission Mount | SuperPro Anti Lift Kit | H&R ARB's | Bilstein B12 | TT Short Shifter |Mintex M1144 Race Pads | HEL Braided Lines |

MK5 GTI - DSG + Extras (Sold because DSG was Soooo Boring !!!)


Offline banksy21

  • Always Involved
  • ****
  • Thank You
  • -Given: 0
  • -Receive: 4
  • Posts: 85
    • Email
Re: cheap pre de-cat
« Reply #8 on: August 27, 2014, 07:47:52 pm »
i chopped the reducer off and used a 3" pipe coupler to join the decat to my piper exhaust.

Offline akbarirfan

  • Won't Shut up.
  • *****
  • Thank You
  • -Given: 81
  • -Receive: 18
  • Posts: 530
Re: cheap pre de-cat
« Reply #9 on: August 28, 2014, 10:55:10 pm »
Did you heat wrap it too?

Offline howie1987

  • Won't Shut up.
  • *****
  • Thank You
  • -Given: 92
  • -Receive: 20
  • Posts: 527
    • Email
Re:
« Reply #10 on: August 28, 2014, 11:19:20 pm »
Don't know if its any use but i have removed my precat and will be selling my down pipe and cat now as of next week as ive got a milltek full system to go on.

Offline banksy21

  • Always Involved
  • ****
  • Thank You
  • -Given: 0
  • -Receive: 4
  • Posts: 85
    • Email
Re: cheap pre de-cat
« Reply #11 on: August 29, 2014, 09:47:17 am »
Did you heat wrap it too?

I didnt wrap it i got told not to by rtech.

Offline akbarirfan

  • Won't Shut up.
  • *****
  • Thank You
  • -Given: 81
  • -Receive: 18
  • Posts: 530
Re: cheap pre de-cat
« Reply #12 on: August 30, 2014, 07:37:39 am »
Did you heat wrap it too?

I didnt wrap it i got told not to by rtech.

OK thanks...Nige at BCS recommends heat wrapping the dp, will have to do some more research!