Power over refers to a car that "naturally" drifts. To do use this technique, you need a fairly high powered FR or MR car. When you enter the turn, let off the accelerator then when you are about one fifth or one sixth through the corner, get back on the accelerator and steer into the corner. This will cause the rear tires to lose traction. After that, just countersteer accordingly and finish off the turn. This technique is more useful for race drifting, especially in the shallow corners.