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i have heard that replacing the cat converter with a pipe or even gutting it will give better spool up because of less restriction.... (most ppl know this) about 4 years ago when i had an r31 non turbo a guy at an exhaust shop told me that if i removed it my engine would blow up!!

I know this is ludacris but are there any side affects of removing the cat???

i ask this, because my old n/a r31 ran like a pig without the cat (maybe not enough backpressure)

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it will give better spool up, and you may notice a slight power increase without the restriction of the cat converter. it is illegal though for street use, and the fumes are quite bad running without the cat converter, you dont wanna breathe that stuff in :P. you will also get black particle shit all over your rear bumper.

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Years ago I ran my ole VL Commodore without a cat after a nasty incident involving a cattlegrid. (ripped the whole exhaust off from the bottom of the headers.)

Idle was a bit rougher, less power down low but once the revs built up a bit there was shitloads more power.

Also sounded great in underground carparks :D

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