Chip tuning  
If you had to sum up what a chip is, it's a management system, which can alter your engine setup to optimize your cars performance. There are two types of chips, an ECU chip and a fully programmable chip.

The ECU upgrade is not programmable but will increase fuelling, sort out flat spots and give small power increases. Perfect examples of these kind of chips would be by Superchips, which are installed by connecting up a computer to your management system and flashing the rom with the new information. They provide a few extra bhp but have had mixed reports on whether they are worth the £200.

Fully (re)programmable chip
To take things further, you will require a fully programmable chip to completely re-map the engine management system. Enabling you to not only sort out fuelling and get rid of flat spots, but to tuned on a rolling road to make the most of your engine. They kind of chips can be adjusted whenever you like at authorised dealers, so if you get any more engine mods, then getting the chip altered will increase its productiveness further. The best on the market for the GTi is without doubt the Dastek, also known as a Unichip. They can also be used on major engine mods like turbo’s and superchargers.

Article written by Ian Dews. 'Courtesy of Ian from'