[SaabJohan]

You can "chip tune" any car that have an electronic control unit for the engine. What you do is that you simply replace the original hexadecimal code in its memory to another code that suits your requirements, or, well, you modify the code slighly (ignition and fueling maps for example) and put it back.

This can be done by programming the ECU or by replacing the chip (usually an eprom or eeprom).

Well, the replacing part is the easy part, the hard thing is to find out what the different part of the code do, and what you should change it to.

With a NA engine the powergain is usually small, just a few percent.