3.0tdi Quattro with 2.0tdi back box


Registered User
Apr 15, 2013
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hi all, looking for a bit of advice, I have a 2007 3.0tdi Quattro and I’m being offered a pair of rear back boxes for my car however they are from a 2.0tdi. I am told that they will be fine on the car but will need a sleeve to adapt them to fit.
My question is, would these hinder performance or anything else if I got them installed?
Why are you fitting smaller back boxes to your car? . Probably lose a few bhp right at the top end but nothing you would really notice compared with the OE 3.0 TDI system.
Have to say I would not want to be fitting 2.0 TDI back boxes on the 3.0. Have you damaged your current system?
Thanks for reply, I have done a rear facelift conversion and can only find rear system from a 2.0 to facelift.. I asked the seller and he says he checked it will fit without issues. But I just wonder if it will restrict flow or power?
It will be more restrictive as it uses small diameter pipe. Don't think I would be fitting it if it were my car.

There are a few on ebay, just sadly don't appear to have a postage option https://www.ebay.co.uk/itm/AUDI-A6-...7604cb:g:aS8AAOSw~BhbFZFR:rk:14:pf:0#shpCntId

Also don't think they would fit....

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Yes I see what you’re saying good point as to wether there would be obstruction with the 2 pipes having a wider gap, I have the option of 2 back boxes only from a c7 3.0tdi do you think these would be a fairly straight forward swap for a exhaust place to put on?
C7 are a completely different shape, don't think they are going to work at all.
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Would it just be the diameter of the pipe going into the back box for the 2.0 face lift that would be the restriction or the internals of the back box it’s self? Thanks