In some of our past and upcoming articles, we’ve been throwing around the word homologation, and it occurs that we should pause to explain what it means.
THE POLITICS OF MOTORSPORT
Most types of motor racing have complex rules and regulations designed to pit like against like. Competitors are typically divided into classes based on factors like engine displacement, power-to-weight ratio, wheelbase, or list price, so that (for example) a 1,000 cc (61 cu. in.) supermini is running against other 1,000 cc mini-cars, not against 5-liter (305 cu. in.) V-8 sports cars.
Sportsmanship and the spirit of honest competition notwithstanding, such rules are very much driven by money. Motorsport is big business, which gives race promoters and officials a strong incentive to maintain a relatively equal playing field — they want to ensure that audiences get a good show. At that time, however, the publicity value of racing victories and championships gives manufacturers and teams a strong incentive to win even if that means taking what we might politely call creative liberties with the rules.
RACING VS. PRODUCTION
One of the ongoing dilemmas for the various racing officiating bodies is trying to curb manufacturers’ natural temptation to stack the deck with purpose-built engines and other experimental hardware. Of course, some forms of motor racing do have prototype or factory experimental classes, but, at least to our point of view, pitting a one-off engineering special against modified stock cars is more an academic exercise than an exciting race.
A common regulatory tactic to require that race cars be based on a production car. However, especially for smaller manufacturers, the exact definition of “production car” can be hazy indeed, which requires racing officials to set specific rules and minimum standards.
To that end, most (though not all) forms of professional motorsport turn to racing’s international regulating body, the Fédération International de L’Automobile (FIA). The FIA addresses the production question by dividing race cars into a series of groups.
A group is not the same as a class, and there are typically several classes within any group. Rather, each group is a set of rules specifying how many production copies, if any, the manufacturer must build before a car may compete and how closely the competition cars must match the specifications of their production counterparts. (Racing series that don’t follow FIA rules develop their own standards for the same purpose.)
Before a given car is allowed to race in any official event following a specific set of group rules, the manufacturer must first submit detailed specifications of the production car to the appropriate regulating body, along with the manufacturer’s assertion that the requisite number of production cars have been offered for public sale.
This process is called homologation — derived from the Greek homologeo, meaning “to agree” — because the specifications of the competition car must follow those of the production model within the range of variation permitted by the rules. For instance, a given set of rules might require the race car to use the same engine block and cylinder heads as the production car while allowing changes to the valves, camshaft, and manifolds. (FIA group rules are much more extensive than just that, but you get the idea.)
Homologation is a prerequisite for qualification, not a substitute for it. A specific car might be properly homologated and still be disqualified for a given race for having non-homologated components or prohibited modifications.
In certain cases, engines and other components can be homologated separately from the cars themselves. For example, if a manufacturer produces 500 examples of a particular engine and 500 examples of a particular car, race officials might permit the car to be raced with that engine even if that specific combination hasn’t been offered to the public.
Sometimes, a regulatory body will also allow manufacturers to field cars with incremental changes or variations from the original homologation specs. Such “evolution” models usually also have to be homologated, but the requirements are generally lower. For example, the manufacturer might only need to build 250 cars to the new spec even if the original requirement was 5,000 units.
Homologation rules don’t prevent manufacturers from developing purpose-built racing versions of their cars; the rules simply make it more expensive. There have been many examples over the years of features or models offered to the public in limited numbers for the sole purpose of facilitating racing homologation.
Such “homologation specials” are usually rare, expensive, and not necessarily well-suited to normal driving, but they do have a tendency to become coveted collector’s items. Famous examples include the Dodge Charger Daytona and its Plymouth Road Runner Superbird cousin; the fearsome Porsche 959; and the original BMW E30 M3.