first things first: Chipping or remapping is essentially the same. The ECU of your car holds a set of fuel and timing maps. These rely on a number of factors I.E airpressure, temperature, engine temperature, engine load and so on. These maps are pre defined for safe operation. They can be altered for better fuel economy, better driveabilty, or more power. Often the the two last options go hand in hand.
The way this is done is either by opening the ECU and replacing the ROM unit, or; on newer cars, hook up a PC, and alter the content of the ECU.
If this is done in the right way, IE, no checksum errors, the workshop cant tell any difference, but you would have gained a few extra horses and a more sleak/vivid throttle response. Without compromising your warranty.
Hope this helps, or else, feel free to email me at ;
Alfanatic@hoygaard.com
Cheers
Hoygaard