Toyota Prius GT

Fuel economy at normal speeds virtually unaffected by performance potential Toyota Prius GT is a high-performance version of the new Toyota Prius that intends to show the most daring side of hybrid technology. This is a concept car and there are no current plans either to put it into production or to engage in motor sport activities. It has been developed to highlight the sheer versatility of hybrid technology which is not just about low emissions and environmental credentials. It can also be tuned to offer sparkling performance and pure driving pleasure. This will be the first hybrid vehicle ever to have taken part in the Goodwood Festival of Speed, which is a celebration of motorsports history. Throughout this weekend, Toyota Prius GT will be used as an official car by the event's organisers. Furthermore, another unit will be on exhibition at the Toyota Booth, together with the Toyota TF104 F1 car and other Toyota cars participating on the Festival of Speed - the 1993 Toyota Celica Turbo 4WD, winner of that year's world rally championship, the 1992 Toyota TS010 group C car and the Toyota 2000 GT from the American SCCA championship, prepared by Carroll Shelby.

Hybrid on the fast track The Hybrid Synergy Drive powertrain of the Toyota Prius GT has been specifically tuned to deliver sportscar performance. The standard Prius Atkinson-cycle petrol engine has been replaced by the 1.5-litre Yaris T Sport powerplant which provides better response and results in a power gain of 29%, from 77 DIN hp to 99 DIN hp.

The electrical part of the hybrid system has also been uprated. The High Voltage Power Circuit now develops 550 V, a gain of 50 V compared to the street version. This makes it possible to install a more powerful electric motor, which now develops 82 DIN hp on its own - a power output similar to that of a conventional 1.4-litre petrol engine.

To cope with the extra power, the battery has been upgraded to develop 34 kW or 46 DIN hp (a gain of 9 kW / 12 DIN hp) and the generator's maximum speed has been boosted from 10,000 rpm to 12,000 rpm. Furthermore, the state-of-charge control has been tuned to provide more rapid race car response rather than to maximise outright range.

The 1.5-litre engine, in conjunction with the electric motor (which can be compared to an electric supercharger), now returns 145 DIN hp, a figure that beats every other 1.5-litre diesel or petrol unit currently on the market. In addition, specific power comes close to 100 DIN hp per litre.

Improved body and chassis To match the increased power output, the whole suspension system - shock absorbers, springs and stabiliser bars - has been uprated to provide sharper handling and improved grip. In addition, the hybrid battery has been positioned over the rear axle to provide near-perfect weight distribution that a conventional car would struggle to match.

The addition of a front spoiler and side skirts generates extra downforce and provide a more aggressive look.

For racing, the whole interior of the Prius has been stripped out to save weight and replaced by two sports seats, harness and a safety roll cage.

As a result the total weight of the Prius GT is just 1,120 kg, 180 kg less than the production version.

More power and less weight result in significant performance improvements, including 0 to 100 km/h acceleration in just 8.7 seconds. Surprisingly, when the Prius GT is driven at normal speeds fuel economy and emissions are virtually unchanged. This is because the effects of a more powerful petrol engine are counteracted by efficiency gains from the electric circuit and the overall weight reduction.