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  #1  
Old 09-11-2005, 04:31 AM
James Scott James Scott is offline
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Join Date: Nov 2002
Location: Fresno, CA
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Cat...cat...cat!

I guess we have three catalytic convertors in our SVX's. I already replaced the high-flow cat which was majorly trashed (possibly from head gasket failure produced water...?) and making my car to run very poor even after the head gasket replacement! The muffler-man was concerned about the front two (2) cats that are part of each side's exhaust manifold (which Y into the high-flow cat. I think I sense a slight strain noise (major when high-flow cat was clogged!) still upon acceleration! SOOOOOooooo.....Should I replace those two cats (about $175 apiece) to be safe...? If one or more is bad (or about to be), they could cause the high-flow cat to fail AGAIN! ......And the head gasket could be blown (or WORSE) with the resultant clogged exhaust! Please advise.. . . .

THANKS!
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1995 Laguna Blue SVX AWD L - 240K (daily driver) - "ReBuILT" used engine at 236K miles (6/13)
2013 Veloster Red - Driver Now??Dropsprings [1/2" rear, 1" front] with Koni Strut Inserts> Magnaflow Exhaust System> ECUTune Stage 1av1 Upgrade (from 1v4)> ECUTune TCU MOD> Aluminum Crankshaft Pulley> Stainless Brake Lines> Phenolic Spacers> Perforated Brake Rotors (dint like, OEM now)> SmallCar Shift Kit (resting since TCU MOD)> 7-Position Ground System> High-Pressure Fuel Pressure Regulator (resting)> ATF Cooler & Campaign Filter> Yellow Polish Polyurethane Bushings> Pioneer Double-DIN Stereo with JL AUDIO Speakers> Driveshaft Rebuilt with C-Clip U-Joints> 15 Min MOD> 20 Min MOD .. . (2011)
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  #2  
Old 09-11-2005, 05:53 AM
svxsvx
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take a different approach

James,
I appreciate I dont know your laws as far as modifications go but if you have the need to replace something you also have the opportunity to improve something. The standard SVX exhaust set up (apart from the exhaust manifold) is a dog. Get yourself down to a performance based exhaust specialist and look to minimise as much of the original crap as you can (still complying with your laws). Off the line speed suffers a little but acceleration over the power band and the note makes it worth while.
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Old 09-11-2005, 07:48 AM
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thundering02 thundering02 is offline
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Unfortunatly for you being in California you have to have all three cats in order to even pass emisons inspection. Otherwise you have to get somebody with a little more knowledge on cat's to tell you otherwise.
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  #4  
Old 09-11-2005, 01:20 PM
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Beav Beav is offline
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Most replacement cats are rated to replace not only the main cat but also the pre-cats. If yours are so rated you could 'gut' the pre-cats with a steel rod and hammer then bolt the exhaust back up, leaving the original shells in place. As long as it blows good numbers and it appears to have the OE cats in place...

p.s. bad precats won't damage the main cat.
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  #5  
Old 09-12-2005, 06:49 PM
James Scott James Scott is offline
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Location: Fresno, CA
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CATS galore!

Beav...A good idea!...BUT, noone will do it! They could lose their license.. .
So, I have to put 2 new front cats to have piece of mind.. . . or just hope for the best..and chance that it's OK..and that it will stay that way awhile! He said they (the fronts) are stainless inside (not like the regular other, incl. high-flow rear cats which are ceramic)? He will charge $180 apiece installed.

PLEASE SHARE ANY OTHER IDEAS you may have, guys.. . .

THANKS!
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1995 Laguna Blue SVX AWD L - 240K (daily driver) - "ReBuILT" used engine at 236K miles (6/13)
2013 Veloster Red - Driver Now??Dropsprings [1/2" rear, 1" front] with Koni Strut Inserts> Magnaflow Exhaust System> ECUTune Stage 1av1 Upgrade (from 1v4)> ECUTune TCU MOD> Aluminum Crankshaft Pulley> Stainless Brake Lines> Phenolic Spacers> Perforated Brake Rotors (dint like, OEM now)> SmallCar Shift Kit (resting since TCU MOD)> 7-Position Ground System> High-Pressure Fuel Pressure Regulator (resting)> ATF Cooler & Campaign Filter> Yellow Polish Polyurethane Bushings> Pioneer Double-DIN Stereo with JL AUDIO Speakers> Driveshaft Rebuilt with C-Clip U-Joints> 15 Min MOD> 20 Min MOD .. . (2011)
Valentine One Radar Detector with Remote Display - ucan'tseeme!
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  #6  
Old 09-13-2005, 09:57 AM
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thumper_svx thumper_svx is offline
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Dunno if this would be legal in Californa, but I replaced my entire exhaust from the engine back to the rear muffler, and in doing so replaced the three cats with two cats from a 3.8L Mustang. MUCH cheaper than the Subaru parts... in fact I think the entire exhaust system cost me less than a single cat for the SVX.

She passed Missouri emissions without a problem after I'd made that change... and it freed up the power a little since it was slightly less restrictive than the stock exhaust (read; slightly bigger pipes).
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