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Is it good to remove catalytic converters?

delcowizzid

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Im surprised it has cats previous model uae cars had no cats and a leaded fuel tune for the super duper arab fuel they have there

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immortality

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No removing them would be bad for your engine

Cats make back pressure with is good and without them you can/will burn out your valves. Don't be cheap a buy hi-flows probably a 200cpi cat as 100cpi cats are illegal too
What a load of crap, go back to school.
 

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The first stage of the local tuning shops package here is headers and exhaust with cat delete lol
Fairly sure that too is now illegal here for too.

edit:Hahaha Deuce beat me to it.
 

immortality

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The cats are only there to reduce emissions, nothing else. Not create back pressure or any other fairy tale.

If it is illegal where you live, then it's totally up to you whether you run that risk or not. Here in Australia it is illegal to remove cats if they were fitted from factory. The reason we have cats in the first place is because pre cat emissions killed all the unicorns. Pretty sure all the people that have either removed their cats or smashed the guts out have made the Western Black Rhino extinct as well.
So what is more deadly, the old leaded fuel or the new fangled unleaded fuel that has a whole lot of other carcinogens?

At least the old leaded stuff fell to the ground once it came out of the exhaust pipe as it was heaver than air.
 

turbodragon

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Not sure why everyone is ripping the dude. Yeah he may be trolling, but would be good to get a genuine answer for future searches by other new members.

I was considering a de-cat pipe to be used for the track (IF I hit the track) and replacing with a high-flow cat for street duties but was unable to find a definite answer in relation to a NA 6L V8.

I made a substantial gain in my R33 GTS-t by using a decat pipe for the track but most of the gains came in the form of the tune (could add a few more degrees of timing due to less restriction). If I remember correctly, I picked up another 20-odd rwkw I think? Bear in mind, this was a turbo'ed straight 6 making 300rwkw on BP 98 and a tad under 350rwkw on E85.

I'm assuming the gains in a NA application will be much less, but more gains would be cominf from the timing advance than the flow increase of remiving the cats.
 

NU13

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Fairly sure that too is now illegal here for too.

edit:Hahaha Deuce beat me to it.
Removing cats is illegal in NZ? A mate has recently got his 07 SS tuned and one of the first things the tune shop did was to remove his cats. I'm getting my 04 SS tuned at another tuner and they say they want to remove my cats as well.
 

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Not sure why everyone is ripping the dude. Yeah he may be trolling, but would be good to get a genuine answer for future searches by other new members.
Yes, a catalytic converter would be a restriction in an exhaust system, just like a muffler. The question is how much of a restriction is is? Modern cats, like a good quality muffler would be a minimal restriction. Running an open exhaust (when tuned for it) will produce more power than a muffled exhaust system, this is fact. However on a street driven car, do you really need that last 1.5% of available power?

I'll happily admit that non of my cars currently have cats fitted, but as mentioned before, here in NZ it was/is legal to remove them from certain vehicles :)

That brings me to high flow catalytic converters, how many would actually meet emissions standard? Fairly sure many don't, but of course, plod looking under the car won't know, not unless your vehicle is sent to get tested.......

Removing cats is illegal in NZ? A mate has recently got his 07 SS tuned and one of the first things the tune shop did was to remove his cats. I'm getting my 04 SS tuned at another tuner and they say they want to remove my cats as well.
It is for vehicles after a certain build date. A couple of years ago the Government changed the emissions laws, they set a specific date/year and only vehicle post that date can be imported now. Fairly sure the same legislation also stipulates that it's illegal to tamper/remove emission control systems on those vehicles.

The thing is, it's not something plod seem to look at here, not yet anyway but they have been known to use sniffers to see who is using leaded fuels......
 

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All this cat removal makes me laugh, it's a stock N/A engine, removing the cats will make 2 fifths of #### all difference.
 

ari666

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That brings me to high flow catalytic converters, how many would actually meet emissions standard? Fairly sure many don't,
mate, most factory cats BARELY scrape through the emissions tests we put them through for approval. some have even had to have additional cats fitted. those BS "high flow" cats would never pass in a million years.
 
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