You will hear the k16 compressors when the spool, shouldn't be too much louder than the header/exhaust setup you have. 450hp I don't see why that would be out of the ballpark by any means. I used to have a biturbo audi and the amount of gains that can be made with turbos is insane. For instance with 2.7 litre engine and twin KO4's people were seeing 420+ HP and an equal amount of torque. The setup looks amazing btw:
