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Author Topic: Edition 30 pre-cat mod  (Read 3832 times)

Offline rickyquicky

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Edition 30 pre-cat mod
« on: May 15, 2013, 08:41:53 pm »
Hi all, new owner here!

Will be posting an introduction as soon as i've cleaned the car and take some decent pictures.

At the moment i'm reading up and planning the mods I want to do to the car. One of the first is to remove the pre-cat from the exhaust system.

I've read that you can take the downpipe off and hack the stuff out, but I would rather buy some sort of replacement. Are the pre-cat and cat part of the same pipework? Or is there a join between them?

The reason I ask is because ideally I would like to just buy a piece of pipe to replace the whole pre cat section, but still keep the standard cat. Have read a fair few threads and am presuming that there is no join between them and therefore not as simple as buying a replacement pipe?

Thanks in advance  :happy2:
« Last Edit: May 15, 2013, 09:29:48 pm by rickyquicky »

Offline rickyquicky

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Re: Edition 30 pre-cat mod
« Reply #1 on: May 16, 2013, 08:34:58 pm »
From what i'm reading online it seems the the pre-cat and cat are all 1 piece, therefore it's not as simple as buying a replacement pipe for the pre-cat that will just bolt on to the standard cat...is that correct?

If that is the case is it best to take the whole lot out and get a pipe welded in place of the pre-cat?

Offline Tamiyoman

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Re: Edition 30 pre-cat mod
« Reply #2 on: May 17, 2013, 03:55:59 pm »
The pre-cat is a just some grey stuff that looks like concrete, just chisel it out carefully and you don't need to change pipework
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Offline vag12

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Re: Edition 30 pre-cat mod
« Reply #3 on: May 17, 2013, 03:59:35 pm »
I am a bit confused, I have 3" blueflame TBE is it possible for me to have a precat still?

Offline GrayMK5GTI

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Re: Edition 30 pre-cat mod
« Reply #4 on: May 17, 2013, 05:13:04 pm »
All your information on pre-cat removal right here:

http://www.mk5golfgti.co.uk/forum/index.php/topic,41083.0.html
NOW: 2015 Golf R DSG 5 Door, Lapiz Blue, 19s, Discover Nav, Reversing Camera
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Offline 56OctyVRS

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Re: Edition 30 pre-cat mod
« Reply #5 on: May 17, 2013, 08:13:02 pm »
I am a bit confused, I have 3" blueflame TBE is it possible for me to have a precat still?
You won't have the pre cat in your aftermarket exhaust.
Frozen White Ford Focus 1.6 Ecoboost Titanium.
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Offline rickyquicky

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Re: Edition 30 pre-cat mod
« Reply #6 on: May 17, 2013, 11:32:48 pm »
The pre-cat is a just some grey stuff that looks like concrete, just chisel it out carefully and you don't need to change pipework

Yeah I know it can just be chiselled out but the shape of the remaining piece doesn't exactly look good for flow. A piece of pipe in its place would be much better than just a gutted pre-cat. It's just a better way of doing things IMO.

Offline Tamiyoman

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Re: Edition 30 pre-cat mod
« Reply #7 on: May 23, 2013, 11:55:54 am »
The pre-cat is a just some grey stuff that looks like concrete, just chisel it out carefully and you don't need to change pipework

Yeah I know it can just be chiselled out but the shape of the remaining piece doesn't exactly look good for flow. A piece of pipe in its place would be much better than just a gutted pre-cat. It's just a better way of doing things IMO.

A better way of doing things is to save up and buy a Full turbo back exhaust, replacing a bit of pipe at front aint gonna do much other than cost you time/money, most of the restriction is the pipe size and silencers, either take pre-cat out and leave at that or replace whole system, better still remove pre-cat for now and save for a full system  :signLOL:
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Offline rickyquicky

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Re: Edition 30 pre-cat mod
« Reply #8 on: June 14, 2013, 12:05:36 am »
Took my car into powerflow in Bromley today on the recommendation that the guy there is good and could cut out pre cat and put some pipe work in its place.

Wanted to stay close to oem but make a worthwhile improvement to an otherwise standard system.

2 hours later and it was all done. Welding is top notch.

No chiselled out pre cat (which I thought was only doing half a job really), and a nice subtle cheap mod. Well happy!

« Last Edit: June 14, 2013, 09:40:16 am by rickyquicky »

Offline patpong_pete

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Re: Edition 30 pre-cat mod
« Reply #9 on: June 15, 2013, 12:04:41 am »
Took my car into powerflow in Bromley today on the recommendation that the guy there is good and could cut out pre cat and put some pipe work in its place.

Wanted to stay close to oem but make a worthwhile improvement to an otherwise standard system.

2 hours later and it was all done. Welding is top notch.

No chiselled out pre cat (which I thought was only doing half a job really), and a nice subtle cheap mod. Well happy!



hi ricky
notice any more power or just the same
also what did he charge for his welding skils

thanks in advance pete

Offline rickyquicky

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Re: Edition 30 pre-cat mod
« Reply #10 on: June 15, 2013, 11:56:39 am »
I don't really know power wise as I haven't had the chance to take it for a proper drive yet, I only really use it 2 miles each way to work lol.

Definatley more low-mid range power/torque. It drives a lot nicer and noticeably pulls better from lower down the rev range, very subtle change in sound too but its hardly noticeable.

It cost £150, but was worth every penny. After it was done and I got home to look at his work properly I was really impressed, nice neat welds and it looks OEM.