On my p38, (looking from the front of the car), take off the battery cover and you have a wide plastic box (black) behind the battery > If I look inside this box (2 screws to remove the lid), there is a super-chip module wired into the other equipment in this box - I was showed this when I bought the car & was told it was the 'chip' to improve the speed of the car.
Also, if your occasionally overtaken by bicycles on the open road, you probably don't have one fitted.