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De-Cat Advice

Dievos
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Dievos Explorer

Dievos

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Just found out that the law doesn't require me to have a cat. so I've decided to get some pipe and make a few flanges. Anything to look out for when i'm doing this? i know there's currently a temp sensor but i just want to cable tie it out of the way for now.

Also, will this give the car a better sound? as it already has a nismo 3" exhaust. is the cat holding me back from a better note?

Cheers

http://www.youtube.com/watch?v=bsIrz_LaHdo

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Carbon 34 Grand Master

Carbon 34

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Pretty sure the law says you need a cat !! If the car came from oem that way , your not going to feel a lot of power over a hiflow car , only noise that makes it sound faster

A decrease if your cat expands pipe goes from 2.5 ,3 to 5in the air turbulence actually makes less power

Plus smells like hell to idle

The fine is huge if your not running a cat or shop removes it for street use

After running no cat on NA rx7 for 11 yrs except for 15 min california style emissions test only to remove it again , on that full race motor i noticed it a lot but the factory intakes etc had to be put back on to pass too and a bottle of emmisions pass junk poured into the tank for the test on bridgeport motor

Its not worth it buy a 100cell for 200 bucks which is sorta legal anyway

Can be drone at speed which is super annoying

My 2 c

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GTR_NUTZ Collaborator

GTR_NUTZ

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I gutted my 3" cat and felt and heard no difference. Kakimoto 3" exhaust.

But there was the occasional bang of a back fire changing gears or just backing off the accelerator.

And yeah I'm pretty sure by law you need to run a cat. I think if the car is pre '85 (or somewhere around there) then no hotdog or cat required, just mufflers.

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Hanaldo Grand Master

Hanaldo

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Carbon 34,

OP is from NZ - cats are not a requirement there, I'm lead to believe.

I thought the same thing, but I believe this has been revised.

http://www.transport.govt.nz/legislation/Vehicle-Emissions-Questions-and-Answers/

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Dievos Explorer

Dievos

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Cheers for the input, the car is registered as a special interest vehicle (used to exempt cars from NZ regulations on frontal impact and emissions) which the R32 GTR classes as.

The car sounds quite droney already and it does occasionally spit when on the overrun and changing gears, see what the story is on the weekend.

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