2004 zhp misfire at high rpms?

So I recently acquired a 2004 zhp automatic to go along with my 330xi. The car has had decent amounts of work done to it, like cooling system overhaul, new spark plugs, fuel filter. The problem is whenever I go to redline the car (6800), the car gets extremely jerky after 6000 rpms almost like its hitting rev limiter or misfiring. I inspected the coil boots and all seem ok, plugs are new. To add to this, the car needs to be set to position 2 for a couple of seconds or else it will result in a long crank (4-5 seconds). Any help is appreciated. Thanks!

2004 zhp misfire at high rpms?