Since launch, the GR Supra has been offered with a straight-six 340 DIN hp/250 kW 3.0-litre engine matched to an eight-speed automatic transmission. True to the GR Supra’s thoroughbred engineering quality, this development has not been simply a matter of using an off-the-shelf solution. A year later, a new 258 DIN hp/190 kW 2.0-litre engine was added to the range, again with auto transmission as standard. Toyota has listened to sports car fans and customers, and can confirm that a new GR Supra with six-speed intelligent manual transmission (iMT) will be introduced in Europe, engineered to delight drivers who love the control and rewards offered by precisely timed manual shifts. Its addition to the line-up means Toyota will offer all three of its GR models available in Europe with manual transmission and three pedals either as standard (GR Yaris) or as an option (GR Supra, GR86).
A new transmission, along with a new clutch has been engineered specifically to suit the power and torque characteristics of the GR Supra 3.0-litre engine. The new-look range also features a special new 3.0-litre Lightweight model. In addition to the lighter weight of the manual transmission, this benefits from further specification changes to cut the car’s kerb weight by almost 40 kg, adding to the car’s handling agility. At the same time, the GR Supra’s braking control systems and suspension have been retuned for even better performance – changes that are being introduced throughout the model range. While the car and its performance have received high praise worldwide from media and fans alike, perhaps inevitably the question of whether a manual gearbox would be available persisted.
The GR Supra’s traction and braking have been optimised for operation with manual transmission. With an automatic, it’s possible to use second gear when pulling away uphill when opposite wheels are on surfaces with different grip levels – for example, when the car is parked partly on an icy road margin. Progress is smooth with no rolling back or wheel slip. With a manual gearbox, first gear has to be used and releasing the clutch brings a greater risk of wheel spin. To address the issue, Toyota engineers have tuned the car’s traction control (TRC) to achieve smooth operation like that experienced with the automatic. The system is also optimised for the GR Supra’s characteristic high engine torque, wide tyres and rear-wheel drive. The car’s behaviour when accelerating out of a corner is a key element in the “Fun to Drive” quality Toyota has developed for the GR Supra.
For the new manual version, the traction control has again been the focus of measure to ensure an ideal balance of agility and stability when exiting a corner on the throttle. TRC intervention has been calibrated to maintain stability – the car keeping faithfully to the driver’s intended line – while allowing the right amount of power for a sporty feeling. The ambition to make the GR Supra fun to drive in the most demanding scenarios has helped inspire the introduction of a new Hairpin+ function. This is designed to allow more freedom and reward specifically when taking tight bends on an uphill gradient (more than 5%) with a high-friction road surface, like those found on European mountain routes. More “free” wheel spin can make such routes more enjoyable to drive, so Toyota has optimised engine torque control to allow a greater difference in the degree of wheel spin on the left and right-side tyres.
The manual transmission installed in the GR Supra has been engineered and tuned specifically for use with the coupe’s straight-six engine. At the heart of the transmission is a newly-engineered clutch with a larger diameter and reinforced diaphragm spring. With a larger friction area and a stronger spring, this new component has the high performance capability appropriate for use with the GR Supra’s high-torque engine. The engineering team were able to modify existing transmission housing, driveshaft and gear set and remove elements that were not required, such as the acoustic package, which further reduced weight. The iMT transmission uses an intelligent control system programmed with new software that prioritise sporty performance. When upshifting, the parameters are tuned to optimise engine torque at the moment of clutch engagement and release; on downshifts, the software has been fine-tuned for consistent performance. The iMT is set as the default, but can be switched off in Sport mode if the driver prefers.
