No it runs completely fine, doesn’t miss fire or nothing, theres not difference in the tone, like it drives completely normal through every gear if you shift before 4k anything after that it doesn’t want to go. I know an exhaust won’t make the car burn oil, just it never smoked that bad with even just a header on, or even the stock exhaust. Which leads me to believe there is shit in the exhaust, but that doesn’t account for the burning of oil.
And Hacknik the car has been run with no exhaust at all and it still does it does the hesitation, so exhaust has been check of the list.