Toyota's GR Corolla and GR Yaris Manufacturing Process

author: FutureCar Staff    

Toyota's performance and motorsports division, Gazoo Racing, has imposed a seemingly simple procedure on the assembly line of the GR Corolla and GR Yaris models to improve the precision of final chassis adjustments. By using a large turntable to redirect the freshly minted cars onto an alignment rack, the need to turn their steering wheels is eliminated, minimizing uneven loads on the suspension bushings. This attention to detail is unusual for a major manufacturer, but it reflects Toyota's commitment to producing racing-inspired driver's cars.

The GR Corolla, introduced for the 2023 model year, is the result of former CEO Akio Toyoda's vision. With all-wheel drive, a 300-hp turbo inline-three engine, and a close-ratio six-speed manual transmission, this sport compact is a larger version of the GR Yaris, which serves as the basis for Gazoo's top-tier World Rally Championship race car. The GR Corolla's performance and starting price of $36,995 have earned it accolades and a place among Toyota's best performance machines. Both the GR Corolla and GR Yaris are produced at the same facility that previously built the Lexus LFA.

Compared to other assembly lines at the Motomachi factory, the Gazoo Racing factory's daily output of GR Corollas and Yarises is relatively small. To accommodate this low-volume operation, the factory uses specialized workstations arranged in semipermanent cells. Electric power tools are used instead of compressed air to lift and locate heavier subassemblies, reducing costs and complexity. Autonomous tugs help shuttle partial vehicles from station to station, eliminating the need for bulky conveyor systems. Workers manually check the machines' output and push body shells around on dollies.

The GR Corolla's solid feel and precise reflexes are a result of its reinforced structure, which includes nine extra feet of adhesive and 349 additional spot welds compared to its mass-produced siblings. The body shell is constructed on a single jig, tightening its tolerances. The mounting points for each car's suspension are scanned and measured to match up individual components with complementary variances. This attention to detail in construction is influenced by Gazoo's race car production methods, as Toyoda believes in making GR models fit for the racetrack right from the showroom floor.

Toyota's proving ground outside Nagoya has played a significant role in refining the GR Corolla. The facility's handling course has helped the GR team fine-tune the car's performance and generate smiles from enthusiasts. The development process for the GR Corolla included pushing back the car's release by a year to further enhance its chassis and increase its power output. The GR Corolla's painted bodies are lowered onto stationary underpinnings, creating a stronger connection and reducing stresses on the car's structure.

Gazoo Racing plans to continue building future GR models with the same meticulous approach. Former GR boss Koji Sato, who is now Toyota's CEO, ensures that the GR ethos will be upheld. The GR Corolla will continue to be developed, with additional potential hidden in the vehicles. Feedback from racers, including those who competed with an experimental GR Corolla powered by a liquid-hydrogen-burning engine, will be analyzed. Gazoo also plans to offer a range of aftermarket performance parts for its cars throughout their life cycles. While electric models are likely to join the GR lineup in the future, they present challenges in terms of developing their driving characteristics.

The name "Gazoo" was chosen for Toyota's motorsports activities in 2015. Originally derived from the Japanese word for "image," the term now means "garage" within the company, representing a place where engineers focus on a car's details.

The assembled GR Corollas undergo a rigorous verification process inspired by motorsports. Weighted bags are added to simulate passengers and fuel, ensuring accurate steering feel. The rear-axle alignment is set and checked before making any tweaks to the front end. The brake pedal is verified for pressure and progression, followed by additional chassis and suspension measurements. If any figures fall out of tolerance, new components are fitted and the finishing process is restarted. Only cars that pass these tests are taken for a test drive and prepared for shipping.

The GR Corolla represents a dream car for many at Gazoo Racing, who developed the car with a focus on creating something they would want to own. The teachings and passion of the Gazoo team have influenced Toyota as a whole, even if there were some challenges within the company's bureaucracy. The perspective of engineers has changed, thanks to former CEO Akio Toyoda's encouragement to push the limits and break cars during development. The GR Corolla and Yaris are the result of this mindset.

The production GR Corolla and GR Yaris are powered by a turbocharged three-cylinder engine that produces 300 horsepower and 295 pound-feet of torque. The engine is assembled on a separate production line and receives performance-focused attention, including matching the cast-aluminum pistons by weight. The choice of a three-cylinder engine was made for its favorable torque curve and reduced exhaust back pressure compared to an inline-four. The GR Corolla was originally designed to compete in the WRC2 class, and a prototype of Toyota's Rally2-spec customer race car will debut this year.

The Toyota Technical Center Shimoyama, located near the company's headquarters, played a significant role in the development of the GR Corolla. The site includes various test tracks, with the country-road handling course being the highlight. Inspired by Germany's Nürburgring Nordschleife, the course features elevation changes, pavement undulations, and challenging corners. It serves as a playground for chassis engineers to fine-tune the GR Corolla's performance. The facility cost over $2 billion to build and is dedicated to testing and development.

FutureCar Staff