Mad's correct, that these cars are mad lighter to improve performance. The heavier a car is, the more power and torque required to produce the performance of a lighter car. Therefore lightening improves acceleration, and to some extent top speed. It also improves handling. Less weight improves the centre of gravity (usually improved with some modifications as well), and there's less momentum to throw the car around with. Lightening the car is usually achieved by ripping out the non-essentials - all seats (racing seats replace the front two), carpet, additional body work, air con, cruiser control, abs and other weighted objects. Panel work is usually replaced with lighter materials, fibre glass, aluminium, Kevlar and more recently carbon fibre. Additionally, roll cages and strut bars are added to give the car's chassis more rigidity - and the roll cage is also intended to protect the driver in case of rolling over. Engines, too, are heavily modified. Freer reving, lightened fly wheels, heavy clutches, massive turbo's or super chargers, massive inter coolers, practically non-existent exists etc. Modern turbo engines are also over-fuelled to keep the idle high enough so that the turbo is constantly spooling. Most engines are rebuilt after every rally to keep them running. On a side note, modern cars that are built around the rally designs are often high maintenance cars - the Mitsubishi Lancer Evo 8 and 9's were high maintenance cars, in particular there was a 400hp Evo (2 litre engine with a turbo bigger than your head and more lag than some cars can rev) that needed to be serviced every 3000kms. Most of those small hatchbacks (chosen, because the small size of a hatch makes them lighter and more nimble than a larger car) looked like Renaults and Peugeot's. Personally I liked the Audi Quattro in its day. Then there was the Lancia Delta S4 - a crazy rally car. The only thing that was shared with the original road going version of the car (towards the end if their rally life) was the cabin. The rest of the car was made from roll cage style tubing and Kevlar. The engine was both supercharged and turbocharged. EDIT: And I just learnt that the car I bought off my brother, and was receiving tonight was just crashed into.