Author Topic: Exhaust - Needs welded? [answered]  (Read 5315 times)

Offline Rossimac

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Exhaust - Needs welded? [answered]
« on: May 02, 2019, 05:15:20 PM »
Petrol car decided to sound like a tractor today!

Found this at the turbo: cat seems to have disconnected nicely.

Weld it up or is it pressed on?



Cheers for any help!
« Last Edit: May 02, 2019, 05:26:21 PM by Rossimac »

Offline Pudding

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Re: Exhaust - Welding the correct way to go? [video inside]
« Reply #1 on: May 02, 2019, 05:19:11 PM »
Yeah weld it back on!
Black Edition 30 with manually selected cogs, a beefier clutch, some extra boost and them Whiteline thingies, otherwise standard.

Offline Rossimac

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Re: Exhaust - Welding the correct way to go? [video inside]
« Reply #2 on: May 02, 2019, 05:25:20 PM »
The votes are in.

Pudding says weld and so we weld!

Offline Rossimac

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Re: Exhaust - Needs welded? [answered]
« Reply #3 on: May 04, 2019, 01:15:45 AM »
So, my mechanic fitted it as best as possible with as little leak as possible, then tack welded it and then dropped the entire exhaust to perform the full weld.

With the exhaust off, he suggested a pre-cat removal as to him the reason why the pre-cat had separated at this point was due to the pressure pushing it off as the pre-cat ceramic thing was not allowing the flow of gases through.

I said go for it (warning, loud!):



Car is stage 1 already and that's it. Have driven 35 miles so far and holy crap the thing is so much more responsive to get going when you floor it and when it reaches the higher end of the RPM, like 4k+, it seems to deliver the power better.
Stage 1 definitely made the car feel more alive but this yet again has impressed me no end. As a person who knows not that much about engines, exhausts etc. it could be placebo, but it feels like a great upgrade for the cost... I dunno.

Only downside is that after giving it some beans, I can smell exhaust gases but not sure if this is a) a leak in the weld b) normal with this delete c) something else.

Other than that, it's a slightly deeper note up front and you can hear it in the cabin. I'm not of fan of deeper notes but this to me is acceptable, happy enough!
« Last Edit: May 04, 2019, 01:19:12 AM by Rossimac »

Offline The Red Warrior

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Re: Exhaust - Needs welded? [answered]
« Reply #4 on: May 04, 2019, 01:57:01 AM »
I thought the idea when doing a pre-cat delete was to hang the exhaust so that the pre-cat is at the bottom. That way the bits that you break off the pre-cat don’t fall into and get jammed in the main cat.

Offline Rossimac

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Re: Exhaust - Needs welded? [answered]
« Reply #5 on: May 04, 2019, 02:31:03 AM »
I wondered that myself...

Offline v4rley

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Re: Exhaust - Needs welded? [answered]
« Reply #6 on: May 04, 2019, 07:48:26 AM »
^^

If you look about half way through the video when it slighty pans back you can just about see the exhaust is actually upside down  :wink:

Offline Pudding

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Re: Exhaust - Needs welded? [answered]
« Reply #7 on: May 07, 2019, 04:11:05 PM »
I think they break there because it's thin metal + lots of engine movement.  The added boost pressure of Stage 1 certainly wouldn't help with back pressure either!

Yeah, it should be bashed out with the outlet facing the floor really.  A few crumbs backed up onto the second cat isn't the end of the world though.

I think it smells more because you now only have half the catalysing area.  Normally the exhaust from these is pretty odourless with 2 cats (except when cold).
Black Edition 30 with manually selected cogs, a beefier clutch, some extra boost and them Whiteline thingies, otherwise standard.

Offline ljc19630

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Re: Exhaust - Needs welded? [answered]
« Reply #8 on: May 08, 2019, 06:48:52 PM »
De cat it and be done with it


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Offline amanda

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Re: Exhaust - Needs welded? [answered]
« Reply #9 on: May 13, 2019, 02:23:59 PM »
De cat it and be done with it


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The problem with decatting is finding a friendly mot guy!
I know as I have a full decatted car and no one but no one now wants to touch it!!!!!!
 :sad1: :sad1: :fighting:

Offline Rossimac

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Re: Exhaust - Needs welded? [answered]
« Reply #10 on: May 15, 2019, 08:07:59 PM »
De-cat is out of the option as over in Northern Ireland we have MOT test centres and therefore you can rarely get someone you know to do it!

Plus de-catting would sound so crap on this car, or it is just me? Haha

Since getting the pre-cat removed, the car feels alive and I think it's awesome.
Fuel economy seems up. Over 750 miles since I got it done 2 weeks ago and my fuel economy is up from an average of 28/29mpg to 31/32mpg. So, fairly happy with that!

Smell isn't noticeable unless you're stationary for a very long time.

Offline Pudding

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Re: Exhaust - Needs welded? [answered]
« Reply #11 on: May 16, 2019, 09:41:50 AM »
Yeah I'm with you on that.  I can't stand the drone and nasty racket of big bore exhausts and de-cats on 4 cylinder engines.  It's all a bit ricer.   5, 6, 8 & 10 cylinder fair enough, they are musical engines, but on a 4 pot it just sounds like a silencer has fallen off.

Glad the cat bashing worked out for you  :happy2:

Black Edition 30 with manually selected cogs, a beefier clutch, some extra boost and them Whiteline thingies, otherwise standard.