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Can anybody give me advice on how to take the cats out of my RS4.

I took the cats out on my MK4 R32 and used the Baker Electronics O2 replacement sensors, but it seems more complex on the RS4, here in NZ there are no emissions testing when you get a warrant (MOT) so I don’t need them, I am just about to by a Miltek and was thinking of getting the Dahlback downpipes (no cats), do you have to drop the engine to fit new down pipes?

Cheers guys

Milltek do catless downpipes for places that don't require cats.

You don't need to drop the engine but it's not the easiest of jobs

i sent milltek an email last week enquiring about some catless downpipes for my "track car" and they sent me an email back telling me to contact mrc.

My understanding is that you still have the two main rear cats so you don't need the cats on the down pipes unless you're in a country with very strict emissions, hence, decatting. Alternatively I would just get some custom down pipes made. Personally I wouldn't remove the rear cats else your car is going to get mighty stinky aside from pi*#ing off all those greenies in NZld

Thanks Don, NZ makes me laugh, all clean & green but its one of the most Polluted places in the world!

the down pipes have pre-cats and main cats..most owners on here of S and RS models on here have removed the pre-cats from there's..you can do this and still keep your main cats..
the pre-cats sit just behind the turbos but you will still need to take off the downpipes to smash them out...

Personally I wouldn't remove the rear cats else your car is going to get mighty stinky

Nah - I've got no cats at all (Milltek cat-less d/p's and a Milltek dual cat-back) and there is no exhaust gas smells inside or outside my car - it does go like stink though ...

S4TAN wrote:

Personally I wouldn't remove the rear cats else your car is going to get mighty stinky

Nah - I've got no cats at all (Milltek cat-less d/p's and a Milltek dual cat-back) and there is no exhaust gas smells inside or outside my car - it does go like stink though ...

I have to admit mine smell a little bit sometimes.......a mix of rotten eggs and petrol !!!! i love it Yeah!!!

cut the cats open and knock the internals out of them

@steph..your in france and yours smells of ze garlic...

i wonder why milltek wouldnt sell me any cetless downpipes

or even catless...

and they sent me an email back telling me to contact mrc.

i wonder why milltek wouldnt sell me any cetless downpipes

Have you tried getting them through MRC jimbo?

No DTC when running without cats??

Running without cats...: rear lambdas have to be disconnected+ modification on the ECU.

Did have normal milltek back box for just few thousands of miles had to replace them because the filling (rock wool) did come out !!!! the back of the car was cover of it, i had the only RS in the country with an hairy ass!!
and the noise was awfull at the end, had to drive the car with hear plugs on !!
Had some special ones fitted with heat resistant material in it, now it is not too loud inside the car.

Get ready gentlemen, it is pretty loud outside especially under accelerations........Yeah!!!