TOYOTA Australia has taken the wraps off its new GR Yaris-based rally car, the GR Yaris AP4 (Asia-Pacific 4WD) ahead of its competition debut in the Netier National Capital Rally in Canberra, to be held from April 9 to 11.
Two Toyota GR Yaris AP4’s will race in the first round of the Australian Rally Championship (ARC), driven by the factory-backed TOYOTA GAZOO Racing Australia (TGRA) rally team of Harry and Lewis Bates.
The TGRA rally team is managed by four-time Australian rally champion Neal Bates, while eldest son Harry is reigning Australian rally champion and his younger brother Lewis finished runner-up in the 2019 ARC season, the last year that the ARC was run in full.
The new GR Yaris AP4 race cars were built and engineered by Neal Bates Motorsport (NBM) in collaboration with Toyota Australia. This is the first time the car maker has been actively involved in the development of the rally cars.
“This really has been a collaborative effort to help bring these cars to life and we are looking forward to their competition debut next month,” Neal Bates said.
“The design not only gives us a great looking car, but fine tuning the shape of the fenders and bumpers and other body parts using Toyota’s advanced technologies has helped give us an aerodynamic edge,” he added.
“We also worked with TOYOTA GAZOO Racing Europe on the 1.6-litre three-cylinder turbo engines, which have been slightly modified from the standard GR Yaris unit to comply with the AP4 regulations.”
Bates and his team of five, including design director Darryl Bush, Lewis Bates, Sam Elliot, Chris Shore and Anthony Caldwell, spent thousands of hours stripping the original GR Yaris road cars and rebuilding them into GR Yaris AP4 rally cars.
“Together with the compact turbo engine and all-wheel drive system, the GR Yaris is a great base car compared to what we have worked with previously to create rally cars,” Bates said.
“Building these rally cars has really demonstrated what’s at the heart of TOYOTA GAZOO Racing – a performance car brand that directly links to real-world motorsport and takes those lessons and technologies and applies them to its road cars.”
The GR Yaris AP4 has been built to meet category regulations and the cars are similar to the global WRC-2 specification for manufacturer-homologated Rally2 and R5 cars that compete in the second-tier competition in the World Rally Championship.
Under rally regulations, bodyshell components such as doors and the roof of the original GR Yaris had to be maintained, but all other parts can be modified. The GR Yaris’ use of aluminium doors and a carbon fibre roof were perfect for a race car.
Minimum weight for the category is 1230kg and the two AP4 cars NBM is building will come in significantly under that, and will use ballast to meet the minimum requirement.
In respect of the bodyshell, part of the weight saving has come from the use of a fiberglass bonnet and hatch, lightweight 3D printed mirrors and bonnet vents, and Perspex windows for lighter weight and safety.
The competition engine is based on a production GR Yaris and while the block, head and inlet manifold are standard, it uses a bespoke exhaust manifold and 1.5 bar maximum boost turbocharger, fitted with an air restrictor to meet AP4 regulations.
While specific output figures are confidential, Bates said they expect the engine to generate more than the standard GR Yaris’ 200kW and 370Nm. The engine drives through a Sadev six-speed sequential gearbox, with NBM specifying the gear ratios they wanted.
The AWD system is also sourced from Sadev and under the regulations, uses a locked centre differential that splits drive torque evenly 50/50 front to rear.
Apart from the engine, transmission, driveshaft and left-hand drive steering rack that provides tight 1.8 turns lock to lock, all other components for the new GR Yaris AP4 have been made by NBM or sourced locally in Australia.
To cope with the rigours of sustained off-tarmac racing, NBM has added 50mm to the front suspension tower and designed and manufactured all the suspension componentry in-house.
Using Murray Coote Australia (MCA) dampers, it offers 265mm travel in the front and 280mm travel in the rear.
Toyota Australia Chief Marketing Officer John Pappas said it was fantastic to see the GR Yaris transformed into a world-class rally car and was proud that Toyota Australia was able to collaborate so closely with Neal Bates Motorsport on such an exciting project.