you should search... as i am no expert and still learning, i think the backpressure issue is non-existant with a turbo. the exhaust will have no negative side effects.
The turbo itself is an obstruction in the exhaust path and creates plenty of backpressure on its own. Helping the turbo to flow as efficiently... as best as possible will only help... intake and free flowing exhaust. It'll help both power and spool up.
