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If I had the rear cats removed would it make it a good bit louder? Also would it throw a code? Just got a 3 in flowmaster 40, dumping after the axle. like the sound just wish it were a bit meaner sounding.
 

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I'd imagine that it'd be a little louder, more free flowing, and you'd have to do a nonfouler mod on the O2 sensor after the 2nd cat, or else you'll throw codes. :thumbup: Another option would be to gut the pre cat (manifold cat), I think gutting this one doesn't throw codes if I am remembering right. Correct me if I am wrong guys.
 

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If u delete the second cat use a O2 spacer to prevent a CEL, im running a flowmaster 44 with no catsand no CEL's love the sound but a little drone
 

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Only concern with gutting cat is EPA standards being implemented and imposed throughout the states. Not saying it should stop you from working this mod, but if your state imposes noise/EPA rules...you might have to replace cats back to stock.

Might be better option to invest in decent after-market exhaust system (i.e. MBRP, Gibson, etc.) and keep stock parts for re-install when you ever sell/trade...just a thought.
 

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when i installed the headers i had a new dual exh made without the rear cats,
i had no prob with the cel light coming on. there was no O2 sensors after them.
no prob with state insp so far, as long as the fronts are in it seems to pass insp.
 

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For the V8's there are no 02 sensors downstream of the rear cats. You won't get a CEL from removing the rear cats and don't need non foulers.

Without the rear cats it's a little louder, definitely worth it.
 
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