How Do I De-Cat

[PUG406SRI-Turbo]

Basiclly above. I need to know how to do it or get somone else to do it for me i dont get how it works i want a big bang when i accelerate ha?

[Blue406]

This isn't barryboys you know.

[PUG406SRI-Turbo]

Ha Sorry mate i am just a big stuck

[Davva2004]

there's two ways of doing it...

The best way is unbolt your cat from between the downpipe and exhaust system, measure it, then get a pipe made up the same internal diameter as the exhaust pipe with flanges on it that match the flanges on the downpipe and exhaust. This way you can replace the decat pipe with the cat at MOT time as there's no way it will pass emissions regulations without the cat fitted.

The cheapest but dodgiest way is to unbolt your cat, then use a metal bar to smash out all the ceramic honeycomb out of the inside of it then rebolt the empty case up again. BUT you'll need to replace it at MOT time and they ain't cheap - around £500 for a new cat.

Can I ask why you're decatting it? If it's to free up some back pressure then bear in mind that most of the restriction is in the exhaust system not the cat so you'll be better off replacing the whole system with a freeflow system from the downpipe back. If you're going to have a custom exhaust system fabricated make sure they make it with a decat pipe fitted for MOT time, and keep your cat somewhere safe as they can be fragile - if you drop it it'll break inside giving you all sorts of grief.

[niz406]

Or buy a Milltek hi flow sports cat for £300 and have it put on your custom stainless exhaust system... circa £400, so £700 of your pennies for exactly what you want with 10 years warranty on the cat and lifetime on the exhaust

[jameslxdt]

but £300 is almost as much as new cat, just weld in a bit of cheapo pipe for £20

[niz406]

or rent a welder from the hireshop, get 10 baked beans tins from tesco.... value so they are cheap ..... like pennies then weld them together lol

[jameslxdt]

exactly job done, and spend the change on some bp ultimate

[niz406]

LMAO..... and some Meths !

[STALLED]

Is it illegal to de-cat a car over there in the UK because you are tampering with the anti pollution gear?

Joel

[niz406]

A car cannot pass an MOT without one, unless it was built before a certain date !

[Welly]

Is it illegal to de-cat a car over there in the UK because you are tampering with the anti pollution gear?

Joel

There are some issues here. Sometimes the police or the department of transport set up roadside random checks for emissions. If they detected high emissions you could be ordered to have the car fixed and show proof of this with an emissions certificate (the same as you get when you 'MOT' a car over here).

Also, it's fairly easy to detect a car with no CAT just by following it, you can smell the emissions. I suppose if the Police were following you and didn't like the look of you/your car they could pull you and then order an emissions check and make you produce evidence within a certain time limit.

I don't know that it is ''illegal'' as such, I think it is more that by removing the CAT your car fails basic emissions standards and you will be ordered to fix it.

[STALLED]

Yeah it's the same here but we don't have the emissions stations. In NSW we just have the yearly inspection but any decent inspector could pick this up as the car reeks of petrol at idle - one of the downsides of de-catting your car! I believe there is a pretty hefty fine if you do get caught here for such an offence, tis not really worth it me reckons?

[jameslxdt]

all vehicles manufactured after 1st august 1992 had to have closed loop lambda control with a three way catalytic converter, though the testing didnt come into force until the 1st january 1994, but also some cars slipped the net and dont need to have a cat, namely shitty ford, but every car had to take the full test if it was manufactured after 1st january 1994

[Captain Jack]

Hi

Davva's back!