Well.....is there? aus wide, or in nsw?? or is it just a defect.

oh yes. i believe its over 10 grand!

Yea it does damage to the environment so these days that = BIG $$$

ok what about a gutted cat? couldnt you just tell the cops u didnt know and that a previous owner had done it?

Quote: Originally Posted by ATMO_BT1 ok what about a gutted cat? couldnt you just tell the cops u didnt know and that a previous owner had done it? you could try telling the EPA that...its up to them if they believe you or not.

Quote: Originally Posted by ATMO_BT1 ok what about a gutted cat? couldnt you just tell the cops u didnt know and that a previous owner had done it? That could work depending on how long you have actually had the car.

Is there a fine for running no cat converter? LOL I think the technical term is major ass reeming LOL. Expect a huge fine, Australia wide, and possibly have your car subject to extensive emission testing, which could, if it's heavily modified, see it off the road for a very long time. If you know it's not right you should fix it, and save your self the hassel Some original photos have not been recovered yet.

I personally don't think ignorance is a reasonable defence. It might get you out of a fine if your lucky tho.

Gutting your cat is just as 'bad' as a high flow cat. By gutting your cat, gases enter an expansion and then have to pass through a contraction. From a fluid mechanics point of view, this is worse than a high flow cat. Whenever gas streamlines have to change direction, they incur a 'minor' loss. The expansion loss is small enough to be negligable but the contraction loss is pretty bad. If anyone wants to debate this topic, I am happy to make references to an assortment of hydraulic textbooks.

Thats why u remove the cat all together and replace it with a pipe of equal size. Thats if ur gunna gut the cat Just a question, what would be worse from a fluid mechanics p.o.v.. gutting the cat, hi flow cat,blocked cat or a normal working cat. I think the gas hitting a honeycomb'd formation then reacting with it would have more of an impact. I think you just opened up a dicussion that no one was actually talking about anyways haha Some original photos have not been recovered yet.

Well i went to get my emissions test done today and i passed. and my car has a high flow 3 inch cat

OI PAUL, it does have a cat man! i just tapped on it tho...hollow as lol

you dont want the epa to catch u wifout 1 they will **** u over big fines involved Some original photos have not been recovered yet.

One thing about emissions test is that they never do it on the spot... So why dont you keep your good cat as a spare. get another cat for cheap... bung in a broom stick... get rid of the "honeycomb"... but get a pipe welded in because it cures both the hollow sound when you tap it.... and that drone sound when your driving down the highway... it gets pretty annoying If you ever get a emissions test, ya still got your old spare GOOD cat to bolt right in Hope it helps, Cheers, Daz Some original photos have not been recovered yet.

yeah but its not like a hi flow cat is restricting your exhaust that much anyway.

Neuby - Yes the hollow area in the cat will make a flow loss to some degree but nowhere near as much as a full cat with all the honey comb. You made a point about the hollowed out one, but have you ever looked inside a new cat? Its ridiculous. If you feel like referencing some Fluid Dynamics texts, make it a UQ approved text so that way I know I have it. Some original photos have not been recovered yet.

No. 83 Zoom has an interesting article on 'Magic cat'. It looks pretty good and I'll be considering it on my exhaust. I'm not sure if this will help LukeVL, cause I'm at USQ... 'Hydraulics in civil and environmental engineering' 3rd edition by Chadwick and Morfett 'Civil engineering hydraulics' 4th edition by Nalluri and Featherstone. These are the books I used. Chadwick and Morfett I recommend to anyone.

Yeah, I used to have an sss pulsar, had a gutted cat. I had to shut the car up cos the exhaust was way to loud, and upon checking out underneith the car, we saw that the cat had been gutted. I had the choice of leaving it as is and hoping the epa didnt notice, or leaving it, and getting a big fine on the spot (apparently something in the order of $600 I was told) So... mmm, best not to.... and yeah, if your car is modded, it might be off the road for a while if the epa wanna screw ya!