S3 8P Decat Opinions

[JamesW1994]

Probably my second post here relativley new to the forum and being an Audi owner!

I am considering a decat option for my 2010 S3 8P. The car already has a Miltek Cat back system and is stage 1 re-mapped.

Looking to get the forums opinion on decatting. Pros / Cons and even better some personal experience.

I live on the Isle of Man, where there is no such thing as an MOT so its not a consideration for me (our goverment literally does not carry out any yearly checks on cars) and decating is completely legal!

Look forward to seeing the responses!

Cheers,
James

 

[smurfworth]

Probably my second post here relativley new to the forum and being an Audi owner!

I am considering a decat option for my 2010 S3 8P. The car already has a Miltek Cat back system and is stage 1 re-mapped.

Looking to get the forums opinion on decatting. Pros / Cons and even better some personal experience.

I live on the Isle of Man, where there is no such thing as an MOT so its not a consideration for me (our goverment literally does not carry out any yearly checks on cars) and decating is completely legal!

Look forward to seeing the responses!

Cheers,
James

Crack on I say, only ever had a sports cat in mine for the legal side of the insurance because decat is meant for "off road use". If ur insurance is happy with it being de cat carry on, they are a lot cheaper than sports cats to start with. Will have to get it remapped to get rid of the check engine light though, or you could try a lambda spacer which are a bit hit or miss as to weather they work

 

[paddy]

I suppose it depends on the restriction of the cat and the restriction of the smaller bore down pipe. it may be that the cat is not the real problem.

 

[R222cet]

The only 2 things you need to consider then is cost and the noise. I have a milltek catback at the minute and I will be getting a sports cat, the car is just about as loud as id like and a decat would make it even louder.
On the open road i dont really bother but it’s the 5AM wake up call for all my neighbours along with the hassle of an MOT which is the reason for me wanting the sports cat.

 

[ElzLewis]

There isn’t really any cons for having a decat except MOT worries which as you have stated isn’t an issue for yourself so I’d be getting a 3” downpipe as soon as possible then go for HPFP internals and a few others bits and get stg2+ aha!

 

[JamesW1994]

The only 2 things you need to consider then is cost and the noise. I have a milltek catback at the minute and I will be getting a sports cat, the car is just about as loud as id like and a decat would make it even louder.
On the open road i dont really bother but it’s the 5AM wake up call for all my neighbours along with the hassle of an MOT which is the reason for me wanting the sports cat.

Yeah the noise for me is probably where I am most concerned, I don’t mind it going a bit louder than what it is now but I don’t want to be that person who makes a load of noise driving around towns.
Sport cat sounds like it could be a more sensible option. Out of curiosity what sport cats have you been considering? At the moment I constantly have to clear the code P0420 (cat below threshold bank). I am assuming its because of my stage 1 and the fuel burning more lean

 

[paddy]

any power gain will be in the larger down pipe as the cat is not really going to be restrictive at stg 1. Remember the cat is there to save the environment, if we all just decat it defeats the purpose.