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Author Topic: Pre-cat. . . . . REMOVED!  (Read 91161 times)

Offline Timvgti

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Re: Pre-cat. . . . . REMOVED!
« Reply #30 on: February 27, 2012, 10:22:02 am »

Yeah I got 204 on JKM's dyno before then got 210bhp on R-Tech's dyno. I know it's not ideal to compare one reading on one dyno against another reading on another but it's there or there a bouts.

It cost me about an hours labour at my local garage (could cost more if your turbo bolts are tight).

Have you tried Autosol from Halfrauds on the tips? Cleaned mine up nicely  :notworthy:

6BHP gain is nice. Maybe the highest, looking at price versus gains!
Guess a twintake/air intake gives about the same gain, but costs way more.

Any other that did a dyno run with the pre cat removed?
And who experiences better mpg? (Not the main reason why I want it, but would be great!)

Offline Bazgti

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Re: Pre-cat. . . . . REMOVED!
« Reply #31 on: February 29, 2012, 03:47:00 pm »
Am i getting this correct?

You take off the pre cat which is connected to the turbo...
Theres then a chalky lookin substance inside...
You knock it out wi a chisel n hammer...
Re fit n hey presto?

Sorry for bein a tard by the way, jus wana get this right cos may av a bash on sunday.

Offline 56OctyVRS

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Re: Pre-cat. . . . . REMOVED!
« Reply #32 on: February 29, 2012, 04:08:49 pm »
Its as simple as that. I know run an aftermarket downpipe and my oe dp is sat in the cupboard under the stairs. It is a good mod and best bit is that it is free to do.
Frozen White Ford Focus 1.6 Ecoboost Titanium.
Mods so far - Superchips Bluefin, High Flow Air Box

Offline Bazgti

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Re: Pre-cat. . . . . REMOVED!
« Reply #33 on: February 29, 2012, 04:19:55 pm »
So you dont think theres a need for the new gasket n bolts?

Offline vRS_Pagey

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Re: Pre-cat. . . . . REMOVED!
« Reply #34 on: February 29, 2012, 04:51:48 pm »
If the bolts come off okay then just reuse them, I bought 3 spare gaskets, one for the pre-cat removal, one for the Milltek downpipe and one for when I refit OE to sell the car.  I didn't knock out the pre-cat in the end and my mechanic reused the original gasket when he fitted the Milly...... :laugh:  Although it does sound like its blowing but that may be at the join between old and new.  If anyone needs a gasket I will do for 5 quid posted.  :happy2:

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

Offline Bazgti

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Re: Pre-cat. . . . . REMOVED!
« Reply #35 on: March 07, 2012, 03:23:14 pm »
Just bought my gasket. What tools do i need?

Offline Bazgti

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Re: Pre-cat. . . . . REMOVED!
« Reply #36 on: March 07, 2012, 10:36:12 pm »
Anyone?

Offline alackofspeed

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Re: Pre-cat. . . . . REMOVED!
« Reply #37 on: March 07, 2012, 11:19:12 pm »
Just bought my gasket. What tools do i need?

Decent socket set, maybe a ring spanner (depending on your socket sets ability to reach / grip some of the flange nuts), hammer, cold chisel, radial wire brush head in a drill (or similar to remove material from the inner wall of the pre-cat pipe), and a dust mask. Obviously a jack and axle stands too. Easy job, at most an hour for a competent DIY mechanic.

Offline malaroo978

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Re: Pre-cat. . . . . REMOVED!
« Reply #38 on: March 14, 2012, 10:39:13 am »
Hey guys hoping for some help  :smiley:

I'm thinking about doing this on my 1.4 tsi. Couple of stupid (really stupid) questions but try not to judge...  :signLOL:

Right, firstly do I need specific o2 sensor adapters to remove?

Secondly I assume I need the gasket (do I just ask for a turbo to downpipe gasket?) But can I just reuse the rest (nuts/bolts etc)? My engine was replaced 1200 miles ago so I'm hoping that will make it easier.

Last stupid question, wheres the best place to put axle stands? I was going to buy ramps but I've already got stands. Is it ok on the sills using wooden blocks with cut outs? Don't fancy a car on top of me...
 
Cheers
 :drinking:

Offline ssed30

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Re: Pre-cat. . . . . REMOVED!
« Reply #39 on: August 13, 2012, 02:09:39 pm »
I removed the precat on my Edition 30 yesterday.  The turbo pickup difference is amazing - far faster pickup and it sounds better.

The exhaust note is a lot more 'burbly' too and sounds great, really nice when backing off the throttle.

I can report more on mpg later, at the moment it's definitely better but maybe only by 2 mpg.  I did my usual route to work today where I always get 33 to 35 mpg.  I got 36 mpg for the first time ever, but was driving slightly faster today.  So it's good.

I reused all original bolts, nuts, and gaskets.

It's a difficult job on the driveway and took nearly 3 hours, not including food and drink breaks.  It would have taken less time had I not dropped a nut into the engine bay... and then a socket.  Both of these each took around 30 minutes to locate and recover.  lol

The penetrative oil is a must for releasing any seized bolts/nuts.

So in my opinion it is absolutely definitely worth doing.

Offline JMP

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Re: Pre-cat. . . . . REMOVED!
« Reply #40 on: August 13, 2012, 02:23:18 pm »
I also noticed good improvements in spoolup, mileage and power when I did mine. However, Im thinking about maximizing K03 and changing the downpipe to a catted Milltek.. How much is there still to gain (power & tq, driveability etc) if going from gutted precat to a 3" catted DP, or even a catless DP? Has anyone dynoed these things?

Offline Black9

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Re: Pre-cat. . . . . REMOVED!
« Reply #41 on: August 13, 2012, 02:40:39 pm »
I'm planning on getting this done ASAP as well. Hoping to book myself in for stg1 Start of next week. Q is, do I have to get the pre-cat removed before the Stg1 to make the most of the map or will the ecu adapt itself once the pre cat is removed?

Offline GrayMK5GTI

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Re: Pre-cat. . . . . REMOVED!
« Reply #42 on: August 13, 2012, 06:33:39 pm »
Mine sailed through its MOT with it removed also. Best value for money mod there is  :notworthy:
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Offline ssed30

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Re: Pre-cat. . . . . REMOVED!
« Reply #43 on: August 15, 2012, 07:21:30 am »
More info on mpg gains:

I always get 33 - 35mpg on the way to work, I'm now getting 35.5 - 37.5mpg.

On the way home from work I always get 38 - 40mpg, I'm now getting 42 - 44mpg.

Pretty good result!

Offline zerolag

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Re: Pre-cat. . . . . REMOVED!
« Reply #44 on: November 27, 2012, 07:18:30 pm »
Didn't want to start a new thread on this.

Does anyone have any before and after EGT readings by removing the Pre-Cat?

I've gone Stage 2 ECU and don't yet have a downpipe, wondering whether you can get away with just removing the Pre-Cat to keep the temps down?  I'm not overly concerned with the extra HP, but want to keep the extra torque Stage 2 has made but keeps temps down also.