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DECAT DOWNPIPE ?
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Old 03 Nov 2005, 10:55 PM   #1 (permalink)
Young Scooby
 
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DECAT DOWNPIPE ?

ANYONE KNOW PROS AND CONS OF THE DECAT DOWNPIPE IE OPEN NECK OR CLOSED , BOOST SPIKES ECT.
ALSO PRICES
THANKS H
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Old 04 Nov 2005, 08:08 AM   #2 (permalink)
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Re: DECAT DOWNPIPE ?

Quote:
Originally Posted by scoobaroo
ANYONE KNOW PROS AND CONS OF THE DECAT DOWNPIPE IE OPEN NECK OR CLOSED

THANKS H
I found this very helpful, it's the NASIOC Downpipe FAQ thread.

Link :arrow: http://forums.nasioc.com/forums/show...hreadid=445812
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Old 04 Nov 2005, 08:14 AM   #3 (permalink)
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Scoobaroo,

Pro - Increases Power.
Con - Normally fails MOT.

The restrictive exhaust system on the Subaru Impreza basically hinders the engines full potential.

I think replacing the exhaust system with a full de-cat (both cats of classic, all 3 on newage) and aftermarket back box frees up about 35-40 bhp.

As I said above though, it will normally fail an emissions test as part of an MOT.

Prices and styles of downpipe vairy. They are normally pretty much the same though mate. Just remember you get what you pay for...

Rich
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Old 04 Nov 2005, 08:21 AM   #4 (permalink)
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LOL Pete beat me to it!!!
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Old 04 Nov 2005, 03:57 PM   #5 (permalink)
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thats exellent guys, cheers ,
one more thing - if my car is a 1993 do i escape the need for a cat. :?
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Old 04 Nov 2005, 04:12 PM   #6 (permalink)
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LOL, you wish!!!

All cars fitted with catylitic converters as standard are all tested to the emissions Subaru specify...

So yes for an MOT you should need a CAT, however some people have gone through the MOT with none fitted and a properly mapped ECU... 8)
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Old 04 Nov 2005, 05:18 PM   #7 (permalink)
Young Scooby
 
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cheers mate, maybe wait till got new mot then decat
thanks again H
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Old 05 Nov 2005, 10:16 PM   #8 (permalink)
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If it is an import MY93 you don't have to pass a cat test as the car is not listed. MOT rulebook says an exact match, and there isn't one! Post 95 i belive that there are different rules.

You still have to pass the basic emissions test though - which is easier with cats but not impossible without

There is no check in the MOT test to see if any cats are fitted on any car - but real hard to pass without
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Old 06 Nov 2005, 04:36 PM   #9 (permalink)
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thanks amahrap, i to dont think a 1993 import should need to meet the strict emmisions test. i think i will put it to the test
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Old 06 Nov 2005, 04:45 PM   #10 (permalink)
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Don't forget guys the MOT has now been revised...

All well and good putting it to the test, but it is all logged to the MOT mainframe now (i.e. if it fails at one MOT station you car will show up on the entire MOT network as a failire, so I was told). Also you now have to pay for a re-test in most places, where before you could sort it out and they would give you the MOT cert...

The days of de-cats passing is slim indeed...
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Old 06 Nov 2005, 08:11 PM   #11 (permalink)
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265 supplied and fitted open neck.
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