World Rally Cars: Useful Information

Educational

Jan 16th, 2020

World Rally Cars: Useful Information

You probably have heard about World Rally, but you almost certainly never paid attention to what makes a World Rally car. Can any car qualify as a World Rally car? This article will shed light on what World Rally cars are and other useful information you may need to know about them.

A World Rally Car is a vehicle built for racing, in line with the World Rally Championship (WRC) specifications. The majority of these vehicles have ‘WRC’ on their names such as the Hyundai i20 WRC, Mitsubishi Lancer WRC, Subaru Impreza WRC, Toyota Corolla WRC, and Volkswagen Polo R WRC, to name a few of them. The specifications, which were first introduced in 1997, are set and updated by the Federation Internationale de I’Automobile (FIA), the international body governing motorsports. Currently, the 2017 regulations are in use with several changes integrated into the rules. 

The FIA initially required the World Rally cars to be built on standard vehicles with a production run of at least 2,500 units. The rules allow modifications on the base models, including upsizing the engine up to 2.0 litres, using modified suspension systems, streamlining the body aerodynamic, converting into 4WD, improving the rigidity of the chassis, changing to a sequential gearbox, fitting turbochargers and anti-lag systems, and reducing the car's weight to a minimum of 1,230 kg.  The vehicles’ dimensions were also set at 4,000 mm (length), 1,770 mm (width), and up to 1,550 mm distance between the front and rear tracks. As a requirement to control the vehicle’s power, all cars with turbochargers should only use air restrictors not exceeding 34 mm  in diameter, capping the power output to 223.7 kW (300 hp).  

By 2004, the allowable modifications and upgrades included cars equipped with paddle shifts, electronic clutch control, anti-lock braking system (ABS), automatic dampers, ride height control, three active differentials, traction control, and active suspensions. A number of the modification were later prohibited such as fitting of active control in 2006 and using paddle shift.

In 2011, Super 2000 cars were introduced into the racing. The 1.6-litre turbocharged direct-injection-engine replaced the earlier 2.0-litre engine but the air restrictor was reduced to 33 mm in diameter from the previous 34 mm. The use of exotic materials such as ceramic, composite, magnesium and titanium was prohibited unless the component was in use in the base model. The paddle shift system was also later banned, and only the mechanical system was allowed only to be re-allowed in 2015. 

The regulations also reduced the number of differentials to two, rejecting the centre differential and only allowing the front and rear diffs which had to be mechanical. The minimum weight of the rally car was re-adjusted to 1,200 kg when empty and 1,350 kg with driver and co-driver on-board.

In 2017 more changes were introduced in the regulations. The maximum diameter of the restrictor was revised upward to 36 mm, boosting the engine power to 283.4 kW from 223.7 kW. The minimum vehicle weight was revised downward to 1,175 kg empty and 1,325 kg with driver and co-driver on-board. The third differential was re-accepted and allowed to be electronically-controlled but the other differential to remain mechanical.

The specifications for the World Rally car are reviewed and changed periodically. Thus, a car may qualify today but fail to qualify tomorrow. At Carparts.com.au, we keep you informed on all there is to know about World Rally cars, World Rally Championships and other happenings in the motor world. Keep in touch by subscribing to our releases and never miss out.