The "stage 2" chiptuning allows you to get the maximum power from your vehicle by taking advantage of the original engine components. It is mandatory to physically exclude the catalyst for petrol engines or the particle filter for diesel engines, if the vehicle is equipped with it.
It is important that the muffler is completely free, it is indifferent the modification of the series plant or the use of downpipes.
The goal of chiptuning stage 2 is to achieve maximum power, without taking into account fuel economy and engine reliability.