Performance turbo downpipes.

[funkihamsta]

Why.
The stock is already likely to be at least 3 inches diameter, they all still end up going through a narrower exhaust pipe in the end (well unlikely to be greater than 3")
And WHY ARE THEY SO EXPENSIVE? Its a manky iron tube. I see peeps charging £600 plus for prole turbo cars (not prestige makes) so what do they do?

[funkihamsta]

Well the 850 T5 volvo aftermarket downpipe is some £500. I'm just wondering if its a snake oil device as l can't logically see any advantage to a big pipe made of manky iron or a nice custom one when they're the same. And even if its larger, what use is that unless you are going to have an equally large diameter exhaust system throughout?

[funkihamsta]

Well my stock is 3" downpipe to a 2" all the way through exhaust. I 'could' increase it to 3" all the way through but it would sound awful (only 1.7) and as far as l'm concerend would do nothing. Surely a 3" exhaust SYSTEM is only needed for 300bhp applications.