When Toyota announced its return to the World Rally Championship in 2015, the concept of building a rally-inspired sports car was part of the plan. The vision was to take technical knowledge and experience from the highest level of international competition and apply them to a new road car that is also suitable for competition driving, and an affordable proposition for customers. The GR (GAZOO Racing) Yaris is that car, built from scratch and designed to win at highest levels. It is Toyota’s second global GR model, following the successful launch of the GR Supra in 2018. For Toyota President Akio Toyoda, the creation of a sports car made purely by Toyota – the first in 20 years – was a personal ambition. Following on from winning the WRC manufacturers’ championship in 2018, he saw a winning car as being key to achieving global recognition as a true auto manufacturer.
There were basic challenges to be met in terms of technical know-how and creating a car that customers would buy. From the outset, the development team worked closely with Tommi Mäkinen Racing to better understand how their goals could be achieved. It was a detailed and labour-intensive process, but one which has yielded strong results in terms of a car that has an ideal combination of rigid, lightweight construction, an agile and responsive chassis and a powerful yet compact turbo engine. Professional rally drivers, including members of TOYOTA GAZOO Racing World Rally Team, drove the prototype models and provided valuable feedback. Testing was also carried out by Akio Toyoda in his expert role as a Toyota Master Driver. The GR Yaris is built on a unique platform, combining Toyota’s new GA-B platform (which debuted on the new generation Yaris hatchback) and a rear section adapted from the GA-C platform used for the Corolla and C-HR.
The 1,618 cm3 12-valve engine meets the World Rally Championship’s Rally 2 (formerly R5) regulations, following Toyota’s negotiations with the sport’s governing body to allow a three-cylinder format. Atsunori Kumagaya, who led the development project, explained: “We preferred this engine due to its light weight and compact size making it simple to install, while the lack of exhaust gas interference made it easier to obtain power.” The fundamental requirement for the GR Yaris’s engine was a sports unit that would deliver outstanding, powerful acceleration and exhilarating sense of continuous power, in keeping with the car’s “GR” designation. The result is a new, in-line three-cylinder engine with a versatile quality that makes it comfortable for day-to-day driving as well as competition performance.
GR Yaris is as light as a B-segment hot hatch (kerb weight 1,280 kg), yet the power is comparable to C-segment performance models. Acceleration from 0 to 100 km/h can be accomplished in 5.5 seconds, while the top speed is electronically limited to 230 km/h. The unit is in fact the largest-capacity and most powerful three-cylinder engine currently in production, yet it is also the smallest and lightest 1.6 turbo unit. Its maximum power output is 261 DIN hp/192 kW at 6,500 rpm, with maximum torque of 360 Nm delivered from 3,000 to 4,600 rpm – performance on a par with that of a 2.0-litre turbo unit. The development team drew on the knowledge and experience of their TOYOTA GAZOO Racing colleagues to maximise the engine’s potential, adopting a number of motorsports-derived technologies to help them meet their goals. These include a ball-bearing turbocharger, large-diameter exhaust valves and multi-jet oil piston cooling.
The turbocharger is integrated in the exhaust manifold, reducing weight, while control of wastegate bypass gases is used to improve the warm-up efficiency of the catalyst. The controls have been improved so that turbo performance can be fully utilised from low airflow volumes, contributing to excellent acceleration response. An air by-pass valve controls the turbo pressure and prevents surge. The large, cross-flow type intercooler features a long core length and low pressure-loss inner fins to help realise high engine output, responsiveness and cooling capacity. The engine’s single-scroll turbocharger had to be strong enough to deal with high outputs, but using a large-capacity unit risked diminishing performance though turbo-lag. The solution was to adopt wear-resistant abradable seals and a ball bearing to improve the compressor’s efficiency and reduce friction. The controls are positioned close to the wastegate valve so that gas flows on the turbine side, reducing lag when the accelerator is pressed.
It is significant that the brakes fitted to the GR Yaris compare in size to those used by the GR Supra – in fact the front discs are larger in diameter. The system is designed for ample braking ability while maintaining vehicle posture true to the driver’s intentions. At the front there are 356 mm ventilated discs with four-pot, lightweight aluminium callipers; the rear brakes are 297 mm ventilated discs with two-pot aluminium callipers. On the GR Yaris Circuit Pack the front callipers are painted red and decorated with the GR logo. The GR Yaris is fitted as standard with 18-inch cast alloy wheels with a light and highly rigid multi-spoke design, the shape of the spokes reflecting the lines of a traditional Japanese sword. The tyres are 225/40R18 Dunlop SP Sport MAXX 050. The GR Yaris Circuit Pack comes with lighter, forged alloy BBS wheels with a 10-spoke design, shod with Michelin Pilot 4S high-performance tyres, designed for extra grip for high-speed driving stability and control. To ensure the tyres’ full performance potential can be realised, the Circuit Pack features retuned suspension, with stiffer springs and anti-roll bars, adapted shock absorbers, and adjustment to the electric power steering assistance.
