I*ve been using shell v-power 93, so octane isn*t a problem. It could be a combination of all the things folks are mentioning(hopefully not the manifold valve malfunctioning). It was only in the single digits today, so weather could be playing a big factor. However, in my experience, colder temps have helped performance. This is my first turbo charged vehicle though.
I*m thinking it might just be the way this car feels. I took the long home today get more time behind the wheel. If I roll into the throttle around 2500 when the car is already moving, it feels great. If I just stomp on it from a stop, I*m not impressed. It could be that all that torque is dropping off around 4K and the 250 HP just feels meh compared to the 310 ft pounds.
If only Mazda installed a boost gauge so that I could feel better about there not being an actual problem.