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every exhaust joint has a different story a straight through pipe will do this or that bla bla. now i was intendng on using a high flow cat shell but with a pipe straight through the middle, so it appears to be a cat. now i know that it wont pass epa, etc. but will it have any other side effects????

cheers

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cat = no fine if caught

no cat = $10000 fine if defected and they feel like fining u for it, because ur allowing full exhaust emissions into the atmosphere

me, ive got no nothing.........straight through pipe, but my car isnt on the streets

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its really not worth the risk these days, Ive been thru the no cat days. Always worring about getting done over.

Technology is better every day.

A good FULL STAINLESS 3-3.5 inch cat will flow big HP. and its legal.

Unless your making big power over 400RWKW your loss is very small if anything at all.

Thats my 2cents

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cops do not carry the equiptment to test emissions, they have to send you to regency or equivalent to test it.

and if you go to this sorta thing without a cat in.... well thats pretty damn stupid

one thing that will happen with no cat is that you may blow visable flames, which could be bad if there happens to be a cop behind you at the time.

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It depends. Your average patrol car won't carry EPA gear, but if you get busted when the cops are setting up defect stations chances are they will have mobile EPA gear.

Side effects? You'll blow flames. You'll stain your bumper. It will probably smell. You'll constantly be paranoid about getting picked up by the cops / EPA.

Personally, I don't think its worth running test pipes for street use. Modern high flow cats don't restrict that much unless you're making big numbers. Certainly not enough to notice on the street.

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i've said this before but here we go

in one option vid, top-sercet did a test with the apexi cat on there r34 gtr.

they put a dude inside the car and put the exhuast gas into the car and tape up the window rofl

long story short car made 7hp more without the cat (BIG NUMBERS ROFL) - only thing change was the cat

(thats a big number car and it only made 7hp differences)

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If you read through the ADR's you'll find that after a certain period of time, ten years from memory, someone correct me if they know better, its considered financially unviable to keep a car to its required emission levels, in effect it means you can run without a cat imho as its considered part of the emissions..

which really makes me laugh as the cops have no idea about stuff like the ADR's, there was a thing on today tonight a while ago about people being done in chapel street vic i think it was, and they where defecting an old series 1/2 rx7 for having half the emissions pipes blocked up..

yet the ADR's allow for this..

go figure..

Edited by Denver
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ask good exhaust shops about a cat bypass

lighflow cat with a strait pipe that goes around it

so high rpms it will have alot more flow

and for the 3k test for noise and emmissions it passes

my mate has it, 5inch bypass with a highflow (i think it has to be that size to work properly but i dont make exhausts its just hearsay, go ask around)

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