When it comes to motorsport, there are two schools of thought when it comes to making a competitive racing car; either you take an existing car and add motorsport gears, suspension, safety features and performance upgrades, or you build something purely designed for racing.
There are various categories of racing which either favour or outright require one approach or the other, but an unusual type of car caught in between the two extremes is the homologation special.
In certain racing categories such as the British Touring Car Championship or the World Rally Championship, homologation is the process of certifying cars to certain standards within the rules of the championship as well as the rules for selling a car to the public.
Many championships require that any cars entered must also be sold to the public to stop bigger manufacturers from entering dedicated racing machines that cannot easily be made street-legal, with limits on which components can be modified.
Series such as FIA Group A required 2500 identical models of the car being entered, which typically meant that manufacturers took the rules mostly seriously.
However, certain series such as the infamous Group B (which required just 200 models a year) or GT3 (which required just ten a year) allow for so-called homologation specials to exist.
These are not necessarily production cars modified for racing; they are instead racing cars that have been made to fit production specifications and are typically sold based on their racing pedigree.
Some of these have become incredibly successful, such as the BMW M3 E30, the Subaru Impreza Type RA or the famous Ferrari 250 GTO, which transcended their racing roots despite being highly successful vehicles in their own right, whilst others were more unusual and less successful.
The most infamous of these, perhaps, is the Ford RS200, a custom-built racing rally car designed and built purely to meet the regulations, but after a catastrophic accident ended Group B rallying entirely, the car was a commercial failure.
Others were more controversial, such as the Alfa Romeo 155 Silverstone, which was seen as a step too far in cheating the rules by not actually installing the new parts but providing them in the boot to cheat around homologation rules.
