R34 Front/dump Modification.

[R34NRG]

recently had to take off the whole exhaust system and replace back to stock to clear a defect. while i was at this i noticed the top of the front/dump pipe which clamps onto the manifold was 25mm smaller in diameter to the actual manifold mouth. ive got straight 3" all the way and thought wat a waste if im only lettn in X amount.

so i had the thing machined out to be larger. ever since thats happened the car sounds like its got a exhaust leak when i put my foot down. turbo spool is alot louder, car feels way more responsive, but sounds like a rusted old holden, which really puts me off. bringing the car back to the shop tm morning but would like to hear anyones thoughts?

[MANWHORE]

machining the inner part of a pipe should haev no effect on making an exhaust leak sound. I'm guessing that gaskets were not replaced, or botls are lose.

Get them to do it properly

[R31Nismoid]

Bit hard to tell without seeing the dump itself