2016 WRX CVT Transmission

[motorculture]

First adopted into the WRX in 2015, the Subaru Lineartronic™ Continuously Variable Transmission (CVT) has once again been utilised in the mighty 2016 WRX. For the true potential of the WRX’s 2.0L Direct Injection Turbocharged (DIT) Boxer Engine to be transferred to the ground through Subaru’s SAWD system, an effective and efficient transmission is paramount. Previous generation Subaru automatic transmissions have utilised either a 4 or 5 gear planetary gear system, allowing the transmission to shift between set gearing ratios dependant on the engine’s load, and the vehicle’s speed. Subaru’s Lineartronic CVT operates by rotating a steel chain between two variable width hard carbonised steel pulleys, allowing for continuously variable and seamless gearing ratio adjustment. Unlike the naturally aspirated FB20 Impreza which utilises the TR580 transmission, the WRX has adopted the TR690 transmission which has been enhanced and optimised to withstand the extra torque produced by the turbocharged engine. By controlling the primary and secondary fluid pressure’s through the CVT’s chambers, the distance between the two halves of each pulley are variable. By narrowing the width of a pulley, the chain’s rocker pins ride higher within the walls of the pulley, increasing the effective gearing diameter. By controlling and finely adjusting the relative width of the primary and secondary pulleys, the transmission can remain in the ideal gearing ratio for optimum performance and fuel economy. Coupled to a new twin damper torque converter, fluctuations in engine torque are absorbed, allowing for a smoother, quieter ride, with lock up achievable as low as 10 km/h. In Intelligent [I] mode on Subaru’s SI-Drive system, rather than labouring the engine through its rev-range by holding gearing ratios, the vehicle’s engine speed is kept at a relatively constant rate where it is most fuel efficient, with the CVT continuously varying gear ratios to accelerate the vehicle. When Sport [S] mode is selected, the engine and transmission operate in the same manner, however the engine speed is allowed to increase to where maximum power and torque is produced. Should the driver desire a raw and even sportier feel, Sport Sharp [S#] mode can be selected, where the transmission will shift between pre-programmed primary and secondary pulley widths, for a sporty stepped shift. Should the driver wish to take control of the gearing ratios, manual mode can be engaged allowing the driver to use the paddle shifters to shift between six pre-determined ratios when in [I] or [S] modes, or eight ratios when engaging [S#] mode. The engine speed at which the transmission shifts ratios is dependant on the driver’s throttle input.