Did a search but maybe i'm using the wrong search words... I just installed a 3" M2 downpipe on my car and the rest is relatively stock. I just wanted to know from someone with experience if you are supposed to hear the turbos whistle A LOT more with just the addition of a DP? It almost seems as if there is a leak they are that much more noticable! Also on cold start it is chugging and sputtering a lot worse now until the warm up phase is over... is this also supposed to happen?

 

As far as the whistle goes this is normal. The "chugging" I'm not sure about, doesn't sound normal. When was the last time you check/changed your plugs? Sometimes plugs will "miss" until they get up to temp.

Frank