Toyota has unveiled a range of new TNGA-based powertrains, including a 2.0-litre Dynamic Force four-cylinder petrol, a revised hybrid system and a new torque-vectoring all-wheel drive setup.
The new, excitingly-named Dynamic Force Engine has been designed to deliver an impressive 40 per cent thermal efficiency, all the while offering more torque at essentially any speed.
In petrol-only applications, it runs with a 13.0:1 compression ratio and offers 126kW of power, along with 205Nm of torque. It runs a 14.0:1 compression ratio in hybrid vehicles, and makes 107kW and 180Nm.
The 2.0-litre THS II takes some of the technologies from the Prius (with its 1.8-litre hybrid system) designed to take up less space, cut weight and improve thermal efficiency.
Under the skin, the ‘Power Control Unit’ sitting above the transaxle is 20 per cent smaller and 10 per cent lighter than before, while the transaxle itself makes use of a parallel reduction gear. Toyota says the electric motor makes 80kW and 202Nm in the new hybrid system.
The battery (pictured) is a 216V, 6.5Ah nickel-metal hydride unit with 180 cells, up from the 168 cells in the 1.8-litre THS battery.
When you accelerate hard, the system now leans harder on the electric motor and less on the engine, delivering a more linear surge.
Two new all- and four-wheel drive systems have been developed to work with the new powertrains on Toyota’s TNGA underpinnings.
Dynamic Torque Vectoring all-wheel drive is designed for petrol-powered cars, and shuffles grunt between the left and right rear-wheels for sharper handling. Unlike some systems, it’s not brake based – rather than slowing the inside wheel to mimic the effect of true torque vectoring, it actually sends torque to the outside wheel.
When you don’t need all four wheels to be driven, ratchet-type dog clutches on the front- and rear-wheel shafts are used to disconnect the back wheels for better fuel efficiency.
The E-Four system will work with hybrid-powered cars, and uses an electric motor on the rear axle to provide extra traction. A new control system should allow it to better manage traction, and there’s 30 percent more torque on offer from the rear motor.
The new Direct Shift-CVT is the first continuously-variable transmission with a dedicated ‘launch gear’ – designed to make it smoother and punchier at low speeds where belt efficiency is traditionally poor.
Once you’re up to speed, the transmission jumps from gear- to belt-drive. Thanks to the new gear system, Toyota has been able to tune the belt drive for better response at high speed.
Toyota’s new six-speed manual transmission is now 7kg lighter and 24mm shorter than before. Toyota says it’s now among the smallest transmissions in the world.