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Pro

less restriction , potentially more power

Light weight :)

Cons

Illegal.

Environment hazard

Louder

A straight pipe makes way more sense than a bent one in place of a cat.

Couldn't figure that out yourself?

Edited by Ben C34
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Yer i gathered louder and more flow which could mean possible power gains, wasnt sure if it could potentially be harmful to the car in any way, still abit of a newbie so wanna make sure i know what im doing before i do it, i read some where that straight pipes are not good for dailys for some sort of air flow reason which is why i askd any cons about the straight pipe

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For a street car just get a good 100cell cat. You should at least make some effort to keep your car legal and not pollute the environment way more than you have to.

Decat will mean you have much blacker exhaust smoke under power (which is a give away to the cops) and your rear bar will be dirty from it.

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There is one other thing being missed.

Even a high flow cat is a waste of time if it does not meet EPA standards, there are rules to the standards and if you want to meet them expect some sort of restriction, most 100 cells dont pass emissions you may as well have no cat.

Otherwise a straight pipe through a cat shell is the way, looks like a cat but isnt, get called in for a test bolt on a stock cat.

Exhaust notes dont change much (very little) with or without a cat, a cat is not a muffler which is designed to muffel sound, its a chamber with a cell substrate inside.....

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Stock cats, especially on late model cars act as extremely good mufflers. Removing all 4 of them makes a huge difference. A highflow cat on the other hand makes no difference to exhaust noise.

My opinion, run a single 5 inch body 200cpsi euro 3 or 4 cat and enjoy a legal highflow cat that will flow 400+kw. Emissions testing is only going to become more stringent in the future, and a black bar will dob you in instantly.

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