Think it is maybe something to do with the 170 having the DPF meaning it chucks out less junk in the form of black soot particles? Maybe?
d3fy said:
h5djr said:Thats correct. Cars without a DPF have to have the final ouput from the exhaust pointing downwards, those with a DPF can be straight.
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That's interesting - is it actually a requirement from Audi that if it hasn't got a DPF it needs downturned pipes?