Make a donation
« previous next »
Pages: [1] 2 3 ... 12   Go Down

Author Topic: Pre-cat. . . . . REMOVED!  (Read 93613 times)

Offline GrayMK5GTI

  • Global Moderator
  • Just look at my post count
  • *
  • Thank You
  • -Given: 125
  • -Receive: 248
  • Posts: 4165
Pre-cat. . . . . REMOVED!
« on: January 18, 2012, 01:07:58 pm »
I'd seen a lot of posts on Briskoda forum about people removing the pre-cat from the exhaust downpipe (not to be confused with the normal CAT) and seen some great gains in terms of power and fuel economy (some members reporting a gain of 5MPG). Most people do this themselves by removing the 4 bolts by the turbo, remove downpipe and take a hammer & chisel to the pre-cat. I didnt fancy doing it myself so I booked mine it at my local trusted garage (ABP Motorsport in shavington, Crewe) and they did the work in just under an hour :congrats:

After a bit of ECU - adapting (on the bypass) I'm happy to report the following:

- More turbo sound  :drool:
- slightly deeper exhaust note :smiley:
- faster turbo spool up  :happy2:
- pulls harder in the higher revs  :driver:

So to sum up, it's a win-win for me  :star: I'll report back on the MPG effect at a later date.

I should also point out that this WILL NOT CAUSE YOUR CAR TO FAIL AN MOT! (unless the requirements change again). VW fit it to aid cold-start emissions which isn't tested as part of the uk MOT.

It's worthwhile changing the manifold gasket and the nuts while your doing it (parts are only about £8 from vw)

See here for more info, part no's and photos: http://briskoda.net/forums/topic/197778-pre-cat-removed/


Cheers,

Graeme
« Last Edit: January 18, 2012, 01:12:05 pm by GrayMK5GTI »
Logged
NOW: 2015 Golf R DSG 5 Door, Lapiz Blue, 19s, Discover Nav, Reversing Camera
GONE:2007 Black GTI Edition 30 3dr

Offline sub39h

  • Just look at my post count
  • ******
  • Thank You
  • -Given: 189
  • -Receive: 84
  • Posts: 1719
Re: Pre-cat. . . . . REMOVED!
« Reply #1 on: January 18, 2012, 01:10:25 pm »
i'm guessing if you have an aftermarket exhaust, a Milltek or similar, that these don't have pre-cats in anyway?
Logged
2006 Phantom Black A3 2.0T S-Line
DSG | Rear Parking Sensors | MFSW | BOSE | Auto lights/wipers | Half leather
MODS : '09 tail lights | TT vents | Bilstein B14 | RNS-E 2010 | AMI | AKS Tuning custom CAI | Titanium BBS VZs | NQS BBK | WALK | Autotech RARB | Bluemotion aero | Blueflame TBE | Autotech HPFP | MY11 Wing Mirrors | Bluetooth | S3 Intercooler
PLANS: Stage 2+

Offline GarethB

  • Won't Shut up.
  • *****
  • Thank You
  • -Given: 10
  • -Receive: 16
  • Posts: 628
Re: Pre-cat. . . . . REMOVED!
« Reply #2 on: January 18, 2012, 01:19:40 pm »
Sounds good Graeme.

depending on whether you remap beforehand, it would interesting to see if you achieve any power gains on JKM's rollers next month
Logged

Offline Tfsi_Mike

  • Just look at my post count
  • ******
  • Thank You
  • -Given: 241
  • -Receive: 309
  • Posts: 10222
  • Go Large or Go Home
    • Tfsi Mikes Money Pit AKS / TTE / RTech St2+ Cupra
  • My Ride: http://www.mk5golfgti.co.uk/forum/index.php/topic,32721.msg402587.html#msg402587
Re: Pre-cat. . . . . REMOVED!
« Reply #3 on: January 18, 2012, 01:21:36 pm »
Quote from: sub39h on January 18, 2012, 01:10:25 pm
i'm guessing if you have an aftermarket exhaust, a Milltek or similar, that these don't have pre-cats in anyway?

My Miltek didnt  :happy2:
Logged

Offline GrayMK5GTI

  • Global Moderator
  • Just look at my post count
  • *
  • Thank You
  • -Given: 125
  • -Receive: 248
  • Posts: 4165
Re: Pre-cat. . . . . REMOVED!
« Reply #4 on: January 18, 2012, 01:24:18 pm »
Quote from: sub39h on January 18, 2012, 01:10:25 pm
i'm guessing if you have an aftermarket exhaust, a Milltek or similar, that these don't have pre-cats in anyway?

No mate, standard exhaust. Didn't want to go all out for a full exhaust system with a cambelt change due
Logged
NOW: 2015 Golf R DSG 5 Door, Lapiz Blue, 19s, Discover Nav, Reversing Camera
GONE:2007 Black GTI Edition 30 3dr

Offline GrayMK5GTI

  • Global Moderator
  • Just look at my post count
  • *
  • Thank You
  • -Given: 125
  • -Receive: 248
  • Posts: 4165
Re: Pre-cat. . . . . REMOVED!
« Reply #5 on: January 18, 2012, 01:25:59 pm »
Quote from: GarethB on January 18, 2012, 01:19:40 pm
Sounds good Graeme.

depending on whether you remap beforehand, it would interesting to see if you achieve any power gains on JKM's rollers next month

Funny you should say that, it's booked in at R-Tech on Saturday - should get a dyno run before as a comparison though!  :happy2:
Logged
NOW: 2015 Golf R DSG 5 Door, Lapiz Blue, 19s, Discover Nav, Reversing Camera
GONE:2007 Black GTI Edition 30 3dr

Offline GarethB

  • Won't Shut up.
  • *****
  • Thank You
  • -Given: 10
  • -Receive: 16
  • Posts: 628
Re: Pre-cat. . . . . REMOVED!
« Reply #6 on: January 18, 2012, 01:33:21 pm »
ohhh, R-Tech. I've never used them personally, but they've always had a great rep across all the forums.

I'm sure that you'll be happy with the results. Is it just booked in for a map, or are there other goodies in store?

Look forward to seeing how it does on JKMs RR. My car should perform a little better than last time too  :evilgrin:
Logged

Offline GrayMK5GTI

  • Global Moderator
  • Just look at my post count
  • *
  • Thank You
  • -Given: 125
  • -Receive: 248
  • Posts: 4165
Re: Pre-cat. . . . . REMOVED!
« Reply #7 on: January 18, 2012, 01:39:33 pm »
Quote from: GarethB on January 18, 2012, 01:33:21 pm
ohhh, R-Tech. I've never used them personally, but they've always had a great rep across all the forums.

I'm sure that you'll be happy with the results. Is it just booked in for a map, or are there other goodies in store?

Look forward to seeing how it does on JKMs RR. My car should perform a little better than last time too  :evilgrin:

Yes I've heard a lot of good things about them, seem to know a lot about the TFSI's and do full diagnostics before the map.

Nah not going in for anything else, just the custom stage one  :happy2:

Yours should be up on last time with the revo map. Have you got any other mods yet?
Logged
NOW: 2015 Golf R DSG 5 Door, Lapiz Blue, 19s, Discover Nav, Reversing Camera
GONE:2007 Black GTI Edition 30 3dr

Offline GarethB

  • Won't Shut up.
  • *****
  • Thank You
  • -Given: 10
  • -Receive: 16
  • Posts: 628
Re: Pre-cat. . . . . REMOVED!
« Reply #8 on: January 18, 2012, 02:01:45 pm »
Yes, it should hopefully perform a little better than before.

Got several parts sat waiting to be fitted, but finding the time to fit is tricky - especially being an accountant in january!

Hopefully will have a few bits sorted by 11 February in time for the RR day.
Logged

Offline GrayMK5GTI

  • Global Moderator
  • Just look at my post count
  • *
  • Thank You
  • -Given: 125
  • -Receive: 248
  • Posts: 4165
Re: Pre-cat. . . . . REMOVED!
« Reply #9 on: January 18, 2012, 04:36:56 pm »
Quote from: GarethB on January 18, 2012, 02:01:45 pm
Yes, it should hopefully perform a little better than before.

Got several parts sat waiting to be fitted, but finding the time to fit is tricky - especially being an accountant in january!

Hopefully will have a few bits sorted by 11 February in time for the RR day.

Awesome you will have to take me out for a spin!
Logged
NOW: 2015 Golf R DSG 5 Door, Lapiz Blue, 19s, Discover Nav, Reversing Camera
GONE:2007 Black GTI Edition 30 3dr

Offline vRS_Pagey

  • Just look at my post count
  • ******
  • Thank You
  • -Given: 66
  • -Receive: 59
  • Posts: 1577
Re: Pre-cat. . . . . REMOVED!
« Reply #10 on: January 18, 2012, 10:35:53 pm »
I was planning this for my vRS (I think I may have contributed to the post on Brisky)  but I got my hands on a used Milltek down pipe with sport cat for a 200 quid........  :party:
Logged

His: MK2 Black Magic Skoda Octavia vRS Estate
Hers: MK5 Graphite Blue Pearl VW Golf GT140 -

http://www.mk5golfgti.co.uk/forum/index.php/topic,32783.0.html

Offline meady

  • Taking part
  • ***
  • Thank You
  • -Given: 0
  • -Receive: 0
  • Posts: 45
    • Email
Re: Pre-cat. . . . . REMOVED!
« Reply #11 on: January 19, 2012, 06:15:44 am »
So ur telling me the golf gti has a pre cat and a main cat? I thought i had goten away from that when i sold my astra :(
Logged

Offline GrayMK5GTI

  • Global Moderator
  • Just look at my post count
  • *
  • Thank You
  • -Given: 125
  • -Receive: 248
  • Posts: 4165
Re: Pre-cat. . . . . REMOVED!
« Reply #12 on: January 19, 2012, 07:04:35 am »
Quote from: meady on January 19, 2012, 06:15:44 am
So ur telling me the golf gti has a pre cat and a main cat? I thought i had goten away from that when i sold my astra :(

That's right, at least its easy to remove bud  :grin:
Logged
NOW: 2015 Golf R DSG 5 Door, Lapiz Blue, 19s, Discover Nav, Reversing Camera
GONE:2007 Black GTI Edition 30 3dr

Offline vRS_Pagey

  • Just look at my post count
  • ******
  • Thank You
  • -Given: 66
  • -Receive: 59
  • Posts: 1577
Re: Pre-cat. . . . . REMOVED!
« Reply #13 on: January 19, 2012, 10:45:19 am »
Quote from: meady on January 19, 2012, 06:15:44 am
So ur telling me the golf gti has a pre cat and a main cat? I thought i had goten away from that when i sold my astra :(

Yup, the pre-cat filter is located directly after the turbo, so all the hot gases are slamming directly in to a wall!!  It's only there for the European cold emissions test, not a requirement in the UK so no issue with removal!  By getting rid, the gases movement is not as restricted which results in quicker spool up etc.  Obviously the ideal is to change the down pipe which increases diameter, and reduces catalyst material but the pre-cat removal on the OE exhaust is the next best thing.  :wink:
« Last Edit: January 20, 2012, 12:19:20 pm by vRS_Pagey »
Logged

His: MK2 Black Magic Skoda Octavia vRS Estate
Hers: MK5 Graphite Blue Pearl VW Golf GT140 -

http://www.mk5golfgti.co.uk/forum/index.php/topic,32783.0.html

Offline Bogwoppit

  • Always Involved
  • ****
  • Thank You
  • -Given: 5
  • -Receive: 7
  • Posts: 77
Re: Pre-cat. . . . . REMOVED!
« Reply #14 on: January 19, 2012, 08:22:54 pm »
Thought I'd post up my Briskoda photo on here if it helps:
Logged
Pages: [1] 2 3 ... 12   Go Up
« previous next »