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De-cat Pipe

Jolinator

By Jolinator,
in Western Australia

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Steve Grand Master

Steve

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Posted
What category of racing and where?

I'll come and watch.

Hope the poofteenth of a kW power you gain from removing the cat makes a difference.

spoken like someone who has never run a cat-out pipe, they make a noticeable difference to mid range and throttle response.

D1 Garage in SA can get them for you as well www.d1garage.com

Another option is get an exhaust shop to weld a pipe through an old cat, a mate got it done in SA for $40 - bashing the guts out doesnt tend to have the same results from what I have been told (by tilbrook auto and dyno in SA).

gazza, cats are pretty much a standard size on nissan.

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gazza750 Veteran

gazza750

Posted
Posted
spoken like someone who has never run a cat-out pipe, they make a noticeable difference to mid range and throttle response.

D1 Garage in SA can get them for you as well www.d1garage.com

Another option is get an exhaust shop to weld a pipe through an old cat, a mate got it done in SA for $40 - bashing the guts out doesnt tend to have the same results from what I have been told (by tilbrook auto and dyno in SA).

gazza, cats are pretty much a standard size on nissan.

oh well i got a cat pipe here if anyone wants it i feel safer keeping me hi flowcat on in case iget picked up lol

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ix9 Grand Master

ix9

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bashing the guts out doesnt tend to have the same results from what I have been told (by tilbrook auto and dyno in SA).

Yep! It's basic physics I guess eh :) When exhaust gases are allowed to expand a few inches either way (in a bashed out cat) they slow down, then must also rapidly speed up to exit the cat again. Not very efficient, and definitely not as efficient as a straight pipe that maintains the diameter which keeps the gases flowing the same speed.

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Jolinator Proficient

Jolinator

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Pipes mine !!! hehe, Thanks gazza750, lol R34 It is actually going on an track spec r32 to replace a collapsed compliance cat so chill, also just for amusement, take a look at nz they dont have to run cats by law, they have done tests, a car in decent condition with a decent tune can still pass an emissions test, And, after around 60thousand kays, Cats are saturated and filter out nothing if not they add to the emissions, so there,

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