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Replacement cats for Mac catted y?

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Old Aug 10, 2011 | 02:35 AM
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Default Replacement cats for Mac catted y?

Looks like my cats on my Mac catted y are setting codes from what my mechanic told me. What are good flowing cats to match to these headers?
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Old Aug 10, 2011 | 06:05 AM
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can you get away with gutting them? yes, i see where you live.
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Old Aug 10, 2011 | 07:27 AM
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hes in cali ? wont he need them .
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Old Aug 10, 2011 | 04:25 PM
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If I gut them, would I just get them tuned out? This SES light annoys me.
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Old Aug 10, 2011 | 05:14 PM
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Originally Posted by AiDRocks
If I gut them, would I just get them tuned out? This SES light annoys me.
my tuner has that cat code turned off.
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Old Aug 11, 2011 | 11:52 AM
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Mac exhaust/cats isn't Cali/CARB legal anyway. If you're gonna fail the visual you might as well fail the sniffer too.

...and yes you can have the codes turned off so you don't get the SES light. Aside from being illegal of course gutting the cats will also make the exhaust a lot louder and it will smell like gas especially at startup.

Rob (Bad30th)



Originally Posted by ramairetransam
hes in cali ? wont he need them .
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Old Aug 12, 2011 | 04:00 AM
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I been to the same smog.place a few times and the never looked hard under the hood or under the car. Hoping the idiot doesn't know what I changed.
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Old Aug 14, 2011 | 09:12 PM
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So back to the original question... What would be a good replacement for my cats?
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Old Aug 17, 2011 | 03:53 AM
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Nobody?
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Old Aug 17, 2011 | 09:16 AM
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Check out Magnaflow metallic core cats, they aren't very restrictive and work pretty well. I'm pretty sure you need 2.5" in/out for the Mac Y-pipe, but of course measure before ordering anything...

Again, only OEM cats are supposed to pass the visual on the Cali smog check, but most any cat will do a good job at quieting the car down and cleaning up the exhaust (some just flow better CFM than others).

Rob (Bad30th)
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Old Aug 18, 2011 | 03:22 AM
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Thanks Rob! I knew what I was getting into buying these mids. I wanted to less restricted cats. These cars are about 10 years old now and last time they barely did a visual. The tech I assume won't know the original location of the cats. I just need to be able to pass the sniffer.
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