Torque limits

On what things one should do a proper research before dwelveing into reflashing modification??

To check the factory torque limit calibration of the model before modifying the maps??

It's always smart to have some idea of what the engine is capable of supporting in terms of power and torque prior to commencing modifications. Some engines will easily support double the stock power/torque, while others might fail if you increase the torque by perhaps 20%. Enthusiast forums for popular models of car/engine will guide you as to what others have achieved and what is safe.