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Old 04-24-2007, 11:06 AM   #1
WillDenham
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Member#: 76687
Join Date: Dec 2004
Chapter/Region: MWSOC
Location: Danville, Kentucky
Vehicle:
2002 Impreza 2.5 RS
Platinum Silver Metalic

Default Replacement Cat/Exhaust Questions

Alright, well I've been throwing a random P0420 here and there for the past 2,000 miles or so, and I get it cleared only to have it come back a good 300-400 miles later. I have checked all hoses for vacuum leaks, changed my plugs/wires/ and made sure to reset the ECU.

I have been experiencing what feels to me like hesitation higher up in the power band, also heard it called as bucking a little as it will pause and then come back.

I took off my exhaust from the catalytic converter back and I drove around for a little bit, it seems that the problem has indeed gone away. Now, I'm not too keen on having a super loud exhaust, but I most definatly like to have some tone to it.

Now then, are there any cheaper alternatives to an actual Subaru branded Cat that I could get? Maybe a high flow cat to improve some small HP/Torque numbers, or at least give me a bit of that boxer sound.

I know that the 2.5 can't get a true boxer rumble without headers, but I'd most definatly like to look around and see my options. I do NOT want to run a race pipe, but I'm most definatly interested in looking at my options.

Any suggestions?
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Old 04-24-2007, 07:48 PM   #2
piker28
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Location: north nj
Default

cats have a warranty life past the car, call up your local dealer

but aftermarket is stromung, random tech... or buy a cheap ebay hfc and get a muffler shop to make you a pipe with them in it
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Old 04-24-2007, 11:29 PM   #3
GC_Anthony
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Location: N. New Jersey
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00 Impreza 2.5RS
Its all BRP again.

Default

8 years/80K miles.
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Old 04-25-2007, 01:10 AM   #4
ballitch
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Location: salem, OR
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98 cam'd EJ251
Wrx Tranny,slowr than ish

Default

do you have emmisions testing in your area requiring you to pass to get tags? if so, you might want to think about a high flow cat instead of getting rid of it. you could get a borla, or borla knock-off. then buy a high flow cat off ebay with 2.25'' diameter pipe and have an exhaust shop weld the HFC in place of the stock cat(1st cat that is)



~Josh~
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Old 04-25-2007, 12:58 PM   #5
WillDenham
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Platinum Silver Metalic

Default

No emissions here in Kentucky at all. I really was thinking about a high flow cat instead of just getting rid of it anyway. I don't want something super loud, but I most definatly want some sound.

Would the HFC do anything to sound, other than dampen it a bit compared to running straight back?

Like I said, I'm looking for a bit of a power increase and a nice rumbly sound, well what I can get without doing headers.

PS - Car has 85k on it, so no go on the replacement.

It's a 2002 2.5 RS.
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Old 04-25-2007, 01:49 PM   #6
REVNU
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I run a 3" MagnaFlow Spun Metal Cat. Catless was LOUD on my car, and putting in the HFC helped tone it down AND got rid of the smell. The smell didn't bother me much, but I know it would bother the cops if they were behind or next to me.

~ REVNU
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Old 04-25-2007, 02:45 PM   #7
Markcjr
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Arcadia Green

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^^^Revnu, are you running a resonator too, or just the hi flow cat? I was wondering if a Hi flow cat would quiet my exhaust down much. Right now i'm running brullen headers, catless, 5zigen fireball cat back. It's real loud now, so I'm debating to go hi flow cat, or both hi flow cat and resonator.

Thanks

mark

Last edited by Markcjr; 04-25-2007 at 02:47 PM. Reason: ....
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Old 04-25-2007, 08:07 PM   #8
legacy1907
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95 YJ Flat black

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hi flow cat will make it louder not quieter, atleast my random tech did for sure
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Old 04-26-2007, 01:42 AM   #9
WillDenham
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Platinum Silver Metalic

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Quote:
Originally Posted by legacy1907 View Post
hi flow cat will make it louder not quieter, atleast my random tech did for sure
I'm speaking of quieter compared to catless. Unless for some odd reason it acts like a resonator as well.
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Old 04-26-2007, 12:52 PM   #10
REVNU
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2005 WRX Sedan
Aspen White

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I have no resonator, but my muffler is chambered (baffled) so that acts as one I guess. The cat definitely changed the tone of the car it's not as raspy and definitely quieter on the top end. It still gets loud though when I get on it, but that's to be expected.

~ REVNU
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Old 04-26-2007, 03:23 PM   #11
Markcjr
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Location: Truckee, CA
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1998 2.5RS mass hole
Arcadia Green

Default

Thanks,
Yeah, I'm catless now, so I figured the hi flow cat might quiet it down, but that I also might need a resonator too.
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