MK5 Golf GTI

All Things Mk5 => How to Guides / Troubleshooting => Topic started by: Black9 on May 29, 2012, 01:03:25 am

Title: Removing Pre-cat
Post by: Black9 on May 29, 2012, 01:03:25 am: So read a post on here about a member who removed his pre-cat on his gti with stock exhaust.
How Wld I go About doing the same? Is the pre-cat located just after the Downpipe? Is there a sensor in it and if so where would I move the sensor to!?

Can I expect this to free up the revs a bit and add a bit more exhaust noise? Talk to me :happy2:
Title: Re: Removing Pre-cat
Post by: badbwoy27 on May 29, 2012, 03:54:41 am: I've got pre cat delete on my powerflow cat back system.expect more noise and also more power if custom remapping.do a search as this topic has been mentioned a few times. On ko3 golf,stage 1 Rtech map,pre cat delete and itg intake managed 256 bhp and near to 300 torques on there rolling road.next up for me is sports cat. :evilgrin:
Title: Re: Removing Pre-cat
Post by: sideshowfred on May 29, 2012, 09:00:15 am: I did this a week and a half ago and it feels like it pulls harder at higher revs. The precat is before the bend in the downpipe. It took me and a mate about 3 hours all in. Exhaust noise is a little bit more but mostly I hear more turbo. And very loud pops from the exhaust when I change gear within the first few mins of driving. But that depends what rpm you change at.
Title: Re: Removing Pre-cat
Post by: GrayMK5GTI on May 29, 2012, 08:09:54 pm: Quote from: Black9 on May 29, 2012, 01:03:25 am
So read a post on here about a member who removed his pre-cat on his gti with stock exhaust.
How Wld I go About doing the same? Is the pre-cat located just after the Downpipe? Is there a sensor in it and if so where would I move the sensor to!?

Can I expect this to free up the revs a bit and add a bit more exhaust noise? Talk to me :happy2:

Ah your saw my thread :grin:

It's as simple as I mentioned, there are links to pictures on pg 2 IIRC. I got my local trusted garage to do it for me :happy2:

Gray
Title: Re: Removing Pre-cat
Post by: Black9 on May 30, 2012, 11:57:10 am: Will get round To this eventually :popcornsoda:

So many other parts I'm in the process of replacing :sad1:
Title: Re: Removing Pre-cat
Post by: GTI-Ross on December 01, 2012, 04:16:35 pm: Me and a friend had a go at this today, started un-tightening the 1st bolt (one you can see from engine bay) felt real tight, we tried WD40 (left for 10mins) still felt tight.

so heated up with blow torch, got a few turn out of it but still was really tight, my mate said it feels like itmight snap....i have heard a few people mention this

Anyone have a link to get a replacement bolt and seal kit?....or just buy straight from VW

Thanks guys
Title: Re: Removing Pre-cat
Post by: GrayMK5GTI on December 01, 2012, 04:54:24 pm: Bolt and gasket part numbers on my thread, in the general area, probs about page 2 or 3 by now :happy2: