|See I dont think downpipes are as important as bigger intercoolers.
Also like AntiHero said... investing in a 4 bolt 3" downpipe is a dead end and a waste of money IMO unless you are planning on sticking with stock turbos for the LIFE of the car.
As my instructer always told me in my high performance class. "Air is horsepower" More air is more horsepower. Exhaust doesnt produce any horsepower.