July 18, 2007 Last year it was the year of the diesel in motorsport, but a new era dawned on the weekend when Toyota made history by winning the Tokashi 24-Hour Race with its Supra HV-R hybrid race car. It is the first time a hybrid race car has won a competition of any form and Toyota can be expected to build on its position at the forefront of hybrid race machine development given the massive investment it is making in the technology in its road cars.
The 1,080 kg Supra is quite different to roadgoing hybrids as it incorporates a quick-charging capacitor system and relies heavily on the four-wheel energy regeneration system which is designed to efficiently recover a greater amount of the car’s energy during rapid deceleration. The system uses 10kw in-wheel motors in the front wheels in addition to one 150 kW rear-axle mounted electric motor.
In total, the car has a whopping 700 horsepower at its disposal, with 473 bhp coming from the 4,480cc motor and a further 227 bhp from the electric motors – even more importantly, the low down grunt afforded by the electric motors along with the ability to measure and modify the additional torque thousands of times per wheel per second make the car far more controllable than a simple petrol engined vehicle.
The Supra’s success follows an entry last year when Toyota was the first car manufacturer to enter a hybrid vehicle – the Lexus GS450h – into the Tokashi 24-Hour race which finished 17th overall.
By entering hybrid systems into racing events, Toyota engineers hope to discover ways to make hybrid systems, most famously fitted to the Toyota Prius production car, more efficient and lighter. In only the second year of competition Toyota used – with success – the data gained from last year’s race in order to develop a new, special racing unit to the limits of hybrid performance.
