Pictures of Supersprint's RS6/RS7 4.0 TFSI V8 downpipe development and comparison to the stock catted downpipes
If you do not know already know the Audi 4.0 TFSI V8 features top mounted turbochargers you will after taking a look at these photos. The benefit for tuners and aftermarket manufacturers is turbochargers and plumbing that are relatively easy to get to as well exhaust gases that only need to travel a short distance. The design is quite efficient but the factory downpipes can be improved as they integrate large cats (as close as possible to the turbos to heat quickly for emissions) and some large bends.
The Supersprint design straightens these bends out for less restrictive flow and also replaces the cats with freer flowing units. Supersprint will also likely develop catless downpipes for 'off-road' use of course. No dynocharts yet as these are not yet for sale but the 4.0 TFSI V8 is going to have a solid downpipe option which should bring some healthy horsepower gains shortly.
Disassembly and Supersprint exhaust design