Alright guys, my car has been acting up for a while now. I did the cam install about a month ago but this problem goes back before the cam install, i think it could be opti related. Anyways here it is.

When cold and accelerating slowly (quarter to half throttle), keeping the accelerator the same, the car feels almost like it is missing, then, between 3500 rpm and 4000 rpm it feels likes the car gets double the power, it almost squaks the ties when this "magical barrier is crossed". This can be repeated for about 5 mins until the car warms up a little bit, and then i cannot tell if the car is running in the double the power stage or in the missing stage. Does anyone have any ideas?

The car is a M6

 

TTT for the day