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Hello Everyone,

As the title states, I am looking for a set of B7 RS4 Milltek downpipes with 200 cell cats in good condition or better.

Anyone ...PM me please

If not then I suppose I'll have to buy some new ones

I thought the standard Cats were 200 cell...

I think they do away with the pre cat though.

std main cats are 400 if I remember correctly,still fairly restrictive even if you gut the pre cats,surely the flow cant be good through an empty pre cat either?

......and you can get Milltek downpipes with 100 cells cats vs 200 cell ones (I prefer these) too......

do 100 and 200s pass mots?

lengster1 wrote:std main cats are 400 if I remember correctly,still fairly restrictive even if you gut the pre cats,surely the flow cant be good through an empty pre cat either?

Really? I swear Doug at MRC told me they were 200 cell and the pre cats were 600 cell and therefore the most restrictive part... maybe i'm going mad which is quite possible lol...

As far as I was aware, the precats are 400 cell and the main cats are 200 cell. Can't find my reference now, but I do remember whoever told me saying that the stock main cats are actually pretty good - which if true makes it much more viable to get some stock downpipes modified by replacing precat body with straight ss pipe and adding an o2 sensor lug after main cat. I bought a pair of stock downpipes off ebay for £60 delivered.

Just my 2p.

TonyHayers wrote:As far as I was aware, the precats are 400 cell and the main cats are 200 cell. Can't find my reference now, but I do remember whoever told me saying that the stock main cats are actually pretty good - which if true makes it much more viable to get some stock downpipes modified by replacing precat body with straight ss pipe and adding an o2 sensor lug after main cat. I bought a pair of stock downpipes off ebay for £60 delivered.

Just my 2p.

Yup, you're right, taken from MRC's website

Precat Removal - From: £489.00

Removal, or gutting, of precats from your standard downpipes. The 400 cell precats are removed leaving your 200 cell main cats giving you a lot less restrictive pair of downpipes. Lambda sensors are left in original positions.

Rick_RS4 wrote:do 100 and 200s pass mots?

I know the 200 cell ones do with the appropriate re-mapping/tune.....as per one of my current RS's

Love all the discussions ladies and gentlemen BUT do you have any downpipes for me LOL

Doc wrote:Love all the discussions ladies and gentlemen BUT do you have any downpipes for me LOL

We're coming up with a better solution for you

Rick_RS4 wrote:do 100 and 200s pass mots?

Mine passed, albeit just by all accounts. Made sure the car was hot first though as I dont have any manifold flaps or SAI.

OP...no DP's for you sorry!

RSKiwi wrote:

Rick_RS4 wrote:do 100 and 200s pass mots?

Mine passed, albeit just by all accounts. Made sure the car was hot first though as I dont have any manifold flaps or SAI.

OP...no DP's for you sorry!

MOT emissions tests must be done at operating temps IIRC - although I'm sure some garages probably don't bother. I'd opt for a "friendly" MOT tester

TonyHayers wrote:

RSKiwi wrote:

Rick_RS4 wrote:do 100 and 200s pass mots?

Mine passed, albeit just by all accounts. Made sure the car was hot first though as I dont have any manifold flaps or SAI.

OP...no DP's for you sorry!

MOT emissions tests must be done at operating temps IIRC - although I'm sure some garages probably don't bother. I'd opt for a "friendly" MOT tester

thanks will be doing a custom exhaust soon but just researching cats and pipe diameter