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Old 08 November 2010, 01:29 PM
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JeffT
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Default Decat Up-pipe on WRX

Hi

Thinking of fitting a de-cat up pipe on my pretty standard UK 2001 WRX Wagon. Its got a 3" Japspeed cat back pipe and back box. Question is, will it still pass emissions tests? Looks like it would still have 2 other cats. What about CEL - any mods needed as current up-pipe has temp sensor in it.
cheers
Old 08 November 2010, 03:38 PM
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bluenose172
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Leave the uppipe alone, fit a sports cat downpipe and decat the rest from there back, then remap.

Last edited by bluenose172; 08 November 2010 at 03:43 PM.
Old 08 November 2010, 04:34 PM
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H2o-uk
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Hi,

Sorry to thread hi jack a bit, but Why not decat the up pipe ? I was under the impression by doing so would increase spool up of the turbo. I have an 03 WRX with decat centre pipe but standard cat in uppipe and downpipe, it has been remapped of course. The reason I asks is that I was toying with the idea of a harveys up pipe to help spool up of the turbo, not really for more power, but lower down torque.

Am I very wrong in my assumption ?
Old 08 November 2010, 04:56 PM
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Scooby_CL
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could you not just put an sti up-pipe on? they dont have the cat in place like the wrx up-pipes do...might be a cheaper option then aftermarket ones.

also yes it does aid spool, the efficiency to which it increases is dependant of the other mods along with the up-pipe though
Old 08 November 2010, 05:01 PM
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bengo
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I wouldn't leave the up-pipe alone. A de-cat uppipe will allow the turbo to spool slightly quicker but more importantly it will save turbo as the cats are known to break up and pass up through the turbo.

A de-catted/sports-cat down-pipe will give you more noticeable power increase over an up-pipe (after a remap) but you'll need to get a de-cat up-pipe also to be safe.

If you just de-cat the uppipe and center section the car should still pass MOT emissions, my bugeye did.

HTH

Ben
Old 08 November 2010, 09:00 PM
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Even the STi decatted up-pipe may not gain you any spool over the stock pipe. Buying an ebay decat up-pipe will rob you of spool.

Last edited by bluenose172; 08 November 2010 at 09:04 PM.
Old 08 November 2010, 10:50 PM
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djandyg
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if you were to decat the centre cat, and leave the up-pipe and downpipe as standard, would u still need it to be remapped?
Old 09 November 2010, 08:57 AM
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JeffT
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Thanks for replies and interest - clearly some divided opinions. May well leave alone for time being - didn't realise this would involve re-maps. Just wanted a "relatively" cheap up-grade and de-cat up-pipe looked A) Cheapish B) Easy to fit and as mentioned, would allow power to come in a bit earlier as the turbo spools quicker. Oh well
Old 16 May 2011, 04:19 PM
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RS_Matt
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Apparently the de-cat up-pipe is a massive job to fit and can take 1-2 days. I've been quoted nearly £500 today for it doing, I'm a few quid short of affording it and one Subaru forum is claiming it's imperative it's the first thing you should do to a WRX. The site also states a decent up-pipe will give 10bhp and spool from 500rpm earlier.
Old 16 May 2011, 04:23 PM
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Originally Posted by RS_Matt
Apparently the de-cat up-pipe is a massive job to fit and can take 1-2 days. I've been quoted nearly £500 today for it doing, I'm a few quid short of affording it and one Subaru forum is claiming it's imperative it's the first thing you should do to a WRX. The site also states a decent up-pipe will give 10bhp and spool from 500rpm earlier.
£500 for fitting up pipe,where in hell you are live matey,this cost average from £60-£100 top in Subaru Specialist.



Jura
Old 16 May 2011, 04:26 PM
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RS_Matt
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Been to two very well respected local Subaru specialist today, I thought it would be £70 tops for a decent pipe and about 2 hours fitting £150 all in!

Old 16 May 2011, 04:31 PM
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Originally Posted by RS_Matt
Been to two very well respected local Subaru specialist today, I thought it would be £70 tops for a decent pipe and about 2 hours fitting £150 all in!

Hi there no way £500 is too much,just have look here for recommended specialist not cowboys or contact here Harvey about the u pipe and will fit as well..


Jura
Old 16 May 2011, 05:00 PM
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RS_Matt
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Just dropped him an email though I understand he's on his death bed

If he's in Darlington that's not too far.
Old 16 May 2011, 05:04 PM
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Originally Posted by RS_Matt
Just dropped him an email though I understand he's on his death bed

If he's in Darlington that's not too far.
But someone must work with him at garage..

Good luck matey.


Search here for people from your area,which tuners are good and which are just cowboys.


Jura
Old 16 May 2011, 05:17 PM
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birchy2010
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It's good mod. I've got the sti up pipe on mine currently as part of a big range I did at once. I'll be selling it in the next month or 2 aswell. Just a pain in the **** to get on and off.
Old 18 May 2011, 02:07 PM
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RS_Matt
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Harvey Smith - £75 to fit an up-pipe! Just waiting on price of up-pipe now.
Old 18 May 2011, 02:21 PM
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Originally Posted by RS_Matt
Harvey Smith - £75 to fit an up-pipe! Just waiting on price of up-pipe now.
Harvey up-pipe is best out there and is proven...
Here are Harvey prices for Up-Pipe

https://www.scoobynet.com/trader-ann...t-uppipes.html



Jura
Old 18 May 2011, 02:34 PM
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RS_Matt
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Pregnant wife lent me the money to get it and I wish I hadn't now.

Last edited by RS_Matt; 19 June 2011 at 10:24 PM.
Old 12 December 2011, 11:57 AM
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how hard is it to get on and off the up pipe on a wrx
Old 12 December 2011, 12:01 PM
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bengo
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Originally Posted by budgie smuggler
how hard is it to get on and off the up pipe on a wrx
Not the easiest job to be honest, especially if the exhaust and turbo hasn't been off already. I replaced mine when I was changing the turbo so it wasn't too bad. Soak the bolts with wd40 before you start!
Old 12 December 2011, 06:20 PM
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Originally Posted by budgie smuggler
how hard is it to get on and off the up pipe on a wrx
Hello mate its not a really hard job just undo the engine mount under the car and jack the engine up a bit and then it will come out with a bit of twisting. I fitted a cheap ebay Toyo sports full dacat system including up pipe around 8 months ago now had a remap by racedynamix making 278 bhp 310tq.There are a few other mods but paid £200 delived, sold the cats on ebay £160 thats £40 for full system . I'm lucky though i have an MOT friend
Old 13 December 2011, 08:37 PM
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Originally Posted by RS_Matt
Apparently the de-cat up-pipe is a massive job to fit and can take 1-2 days. I've been quoted nearly £500 today for it doing, I'm a few quid short of affording it and one Subaru forum is claiming it's imperative it's the first thing you should do to a WRX. The site also states a decent up-pipe will give 10bhp and spool from 500rpm earlier.
I thought it was'nt that long ago you had a thread up, about your up pipe and the fitting of it ?
Old 13 December 2011, 10:02 PM
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Gigsy
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Originally Posted by Scooby_CL
could you not just put an sti up-pipe on? they dont have the cat in place like the wrx up-pipes do...might be a cheaper option then aftermarket ones.

also yes it does aid spool, the efficiency to which it increases is dependant of the other mods along with the up-pipe though
STI, 2.5 WRXs or the up-pipe froma classic... all the same part number
Old 13 December 2011, 10:11 PM
  #24  
Billet
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Originally Posted by Masswithclass
I thought it was'nt that long ago you had a thread up, about your up pipe and the fitting of it ?
This thread is 7 months old.
Old 08 April 2013, 02:20 PM
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adamroutley
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Do you need a remap if you fit an STI Up-pipe to a wrx? I still have the other Cats in place.
Old 08 April 2013, 02:23 PM
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Originally Posted by adamroutley
Do you need a remap if you fit an STI Up-pipe to a wrx? I still have the other Cats in place.
Yes you will need remap plus yours mapper must disable EGT CEL


Jura
Old 08 April 2013, 06:34 PM
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i changed my uppipe for a sti uppipe on my03 wrx. it had to be mapped again for it.
from haveing the down pipe already decated it made no difference in spool up or power but i did loose 8bhp from 298 to 290, but it was mapped good first time round lol. the only benifit i get from a decat system is i can through a flame out lol.
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