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Evening all.
My name is Russ & I have a 2006 wrx sl saloon that I've owned since 2007. She was my daily up in till 3 yrs ago & since then I've only done a couple of k miles, so she doesn' get used much now sadly.
She went in to my local garage today as I heard a blow from the exhaust the last time I fired her up. I knew that the silencer after the cat was on its way out due to age (Its had a prodrive back box since I bought it) so I bought a resonated ss one from scoobyworld to replace it with which they fitted for me (it does seem to knock a little, the resonated part is hitting a bracket for the prop shaft they told me?? I've not had the chance to look myself yet,) , but they have found that the second cat has corroded & appears to have leak as well. It's cracked I think was their exact words.
She was remapped about 7 yrs ago when the air pump & valves started to play up, so I had them mapped out & also took the opportunity to get a little extra go as well as it would have been rude not to eh. It's a fairley conservative map on 95ron done by Duncan at race dynamics, but still goes nicely down the road
So my question is what to do now. Should I remove the second cat (Will I need my map tweeked??) or shall I look for another second hand replacement cat pipe? I dont really fancy paying stealer prices for a new one. A second hand replacement & no map tweek would be my prefered option but finding one might prove toublesome??
Yes that' the offending part. Mines a 2006 WRX 2.5 so I guess that neither of the ones you listed would fit. I'm hoping that someone has a good one laying around that they have changed out due to a decat
Crappy uk roads. They're Inovit cts. I've already had one welded in the past, but noticed another had cracked in the inside of the rim when I took them off to try another set on........OZ chrono but I'm not 100% sure I like them as much yet hence they're back in the garage at the moment. I've had the others for years so I am kind of used to the look.
back to the exhaust......isn't the first one you linked to for a 2.0 Sti....I was under the impression that the 2.0 & 2.5 were different lengths? The same length from turbo to cat back overall, but different lengths for the 2 parts individually so you couldn't mix & match 2.0 & 2.5 ones?....Or have I got that wrong?
Russ,
You may want to remove both cats and replace them with a PPP sports cat. You can pick a decent one for about £250 and they're faily bullet proof. You'll need a remap, but you should see 280bhp and a lot more torque with the OEM turbo.
Tidy motor by the way.
Gio
Thanks Gio.
It's already mapped & tbh I don't really want to get it mapped again if I can get away with it. I hardly use it so I don't want to spend any more money on it than I have to.lol. I had it mot'd Friday as it ran out in March & just sat in the garage . I just looked back over the old mots I've actually only done 623 miles in the last 3 yrs & only 320 since the second cambelt service (at 10 yrs) & fitted new coilovers & all new discs & pads. I should really sell it so someone else can enjoy it, but I hate selling things hence I've owned it for nearly 12yrs.
I guess I'll just have to keep an eye on eBay & contact a few breakers to source a second hand replacement.
I have contacted the seller in the first link that jaygsi posted it's for a 2.0 so not any good for me I don't think.
Last edited by Russwrxsl; Oct 28, 2018 at 12:23 PM.
Reason: Forgot to add
Russ,
The downpipe section comes in two parts, each part has a cat. If you got a both parts from any 2000 - 2006 impreza WRX or STi they'll fit. If you only get one of the parts (ie the second part with the second cat), you'll need to ensure it is from a Hawkeye WRX or STi. It may be easier to find a complete downpipe section with both parts from a newage than sourcing a second part specifically from a Hawkeye.
Try some of the breakers on this forum.
Ta,
Gio
I should have a PPP second cat replacement decat pipe from a Hawkeye WRX
Drop me a message if you're still looking for one
Thanks, I'll drop you a pm for a price matey.
My only issue is that I'm thinking I'll need a map tweek if I remove the second cat? It would be handy if I could get a definitive answer really as it would be yet more cost. It's currently running a map for 1.2bar but on 95ron as that's what I asked Duncan for. I guess my concern would be underfueling & boost spikes due to more flow?
Originally Posted by G10
Russ,
The downpipe section comes in two parts, each part has a cat. If you got a both parts from any 2000 - 2006 impreza WRX or STi they'll fit. If you only get one of the parts (ie the second part with the second cat), you'll need to ensure it is from a Hawkeye WRX or STi. It may be easier to find a complete downpipe section with both parts from a newage than sourcing a second part specifically from a Hawkeye.
Try some of the breakers on this forum.
Ta,
Gio
That's what I thought, so thanks for clarifying it for me.
Right, I've been offered a prodrive decat pipe so thats option 1.
Option 2 would be a new stainless decat pipe instead of an old second hand one.
Also, I didn't know the prodrive decat had a small silencer instead of a cat, whys that?
The only thing I'm concerned about is the implications of removing the second cat on my map. It would be good to get someones experienced answer as to removal of the second cat & if i need to spend yet more money & time getting it remapped again?
Last edited by Russwrxsl; Nov 5, 2018 at 08:58 PM.
Surely you're on borrowed time Jay?
I'm not that brave.lol. I keep reading that the 2.5 suffers with boost spike with more flow? So I guess I should do some data logging at the very least if I go down this route
This is what I've been offered. I didn't know the prodrive one had ant sort of silencer in, but I've not seen one without the heatshield before
Not a clue bud. I'm not too worried. The amount of owners that have modified there Impreza's and never mapped them is insane. Although I'm planning on mapping mine. But the amount I've seen with dump valves and induction kits and exhaust changes and no remaps is very high.
Even seen someone selling one with uprated injectors and turbo with no remap that's crazy.
Think of how many cars out there just get generic remaps. My daily Saab engine has a stage one generic remap. Which Is not customised to the car so surely won't have all correct parameters.
2006 wrx 2nd cat problem
They're Inovit cts. I've already had one welded in the past, but noticed another had cracked in the inside of the rim when I took them off to try another set on........OZ chrono but I'm not 100% sure I like them as much yet hence they're back in the garage at the moment. I've had the others for years so I am kind of used to the look.
. I just looked back over the old mots I've actually only done 623 miles in the last 3 yrs & only 320 since the second cambelt service (at 10 yrs) & fitted new coilovers & all new discs & pads. I should really sell it so someone else can enjoy it, but I hate selling things hence I've owned it for nearly 12yrs. 
