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I've heard a fair bit of talk about hollowing out/punching out the CAT in the hope of gaining some power. Now to me this sounds highly illegal given emission laws but I'd think it'd be hard to tell if done right? Has anyone done this themselves, if so what process, did you open the cat or remove the insides through the holes, did you gain any power? What are the risks etc etc.

Cheers

Well, Looks like all of my original questions have been answered so thanks for all who posted. I think I'll pass on doing this given the balance of the pro's/con's equation. Not really keen on black build up on the rear bar nor do I want the unwanted attention that a flaming exhaust would bring. Environmentally, in all honesty this doesn't phase me, if I was that conscious of the environment I wouldn't drive a Turbo 6, I'd take public transport or drive some kind of rice burner 1.3L - 6L/100k's type car, but I do understand the point of that remark and appreciate the time taken to respond. The fines issue does concern me but I've never heard of someone being handed a 9-10k fine for an infringement, this is not to say that the fine does not exist. The worst I've seen/heard of was 2k for failing an emissions test and of the associates I have with modified cars, only two have ever had to take the car to be tested and they were highly modified examples, and obviously so.

Once again, thanks all for the time taken to respond, I've not seen this topic before and did try searching for it before posting, as I think 'most' of us do :P

Cheers

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From the NSW Clean Air—Motor Vehicles and Motor Vehicle Fuels) Regulation 2002

17 Removal or adjustment of anti-pollution devices

(1) The owner of a motor vehicle who uses the motor vehicle, or causes or allows it to be used, is guilty of an offence if:

(a) an anti-pollution device had been fitted to the motor vehicle, and

(b) at the time of that use the device had been:

(i) removed, disconnected or impaired, or

(ii) adjusted or modified and the adjustment or modification results in the emission of excessive air impurities by the motor vehicle.

Maximum penalty: 400 penalty units in the case of a corporation, or 200 penalty units in the case of an individual.

....but I can't find the current value of a penalty unit :P

I had a straight threw bit of pipe like they sell on ebay as a racing cat the car came with it . I took it out and put a hiflow cat on there. Apparently they can tell (Qld Transport or Police) weather you have had your cat punched out buy putting a probe on the end of the exhaust. so you will get caught either way. Feel free to correct me if im worng :P

I had a straight threw bit of pipe like they sell on ebay as a racing cat the car came with it . I took it out and put a hiflow cat on there. Apparently they can tell (Qld Transport or Police) weather you have had your cat punched out buy putting a probe on the end of the exhaust. so you will get caught either way. Feel free to correct me if im worng

yeah, it works in the same way an o2 sensor does. just reads different things.

Something went wrong in your calculation there Adrian, $550x200=$110,000.

I thought one penalty point =$110 in NSW, so 200X$110= $22,000.

I'm still all b'day partied out from the weekend. ;)

Good job! :P

"It's got a cop motor, a 440-cubic-inch plant; it's got cop tires, cop suspension, cop shocks. It's a model made before catalytic converters so it'll run good on regular gas. What do you say — is it the new Bluesmobile or what?"

Anyone who is seriously dumb enough to take a guttered of piped cat over the pits deserves to be fine for sheer stupidity. I had a piped cat for around 2 years. Did the cop check it..... Nope. but i took it over before going ober the pits. NO COP will pick and be able to prove u have a piped or guttered cat. If they tap and its hollow u just say it must have come out over time (which does happen). If it piped well then u havnt really got a problem cause cops dont exactly carry around temperature guns all the time. And if u do pop a flame infront of a cop.... well ur an idiot.

piped cats are great. Had them before and got them on my car now. NOT one problem eva. (except if u leave any parts of the cat in there they smell like rotten eggs when they burn)

My mates have done it, one on a VL one on an r31 and gained alot of power for something that so far has cost them nothing, I warned them about the epa fine but has anyone actually ever witnessed this enforced? no one I know, but risk vs cost i'm going with a high flow cat mostly because im upgrading from 2.5" standard zaust to a greddy power extreme 3" stainless, but I cant see how a high flow 2.5" cat with the honeycomb interior even with the metal/ceramic inside could possibly flow better or give more power than a 2.5" cat with nothing inside, anyway if you really want to do it all you need is a screwdriver and a hammer pull of the cat, stick the driver inside and smash all the plastic honeycomb until its in bits small enough to shake out, my mates cars sound GOOOOD! to0! :P

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