
SEOUL, South Korea – The Hyundai/Kia partnership has developed what is claims is the world’s first continuously variable valve-duration (CVVD) technology and says it will be installed in future Hyundai and Kia vehicles.
The innovation was revealed alongside the Smartstream G1.6 T-GDi – the first engine to have the technology.
”CVVD,” Hyundai explains, ”optimises engine performance and fuel efficiency and is eco-friendly. The valve control technology regulates the duration of valve opening and closing according to driving conditions for a potential 4% increase in performance while burning 5% less fuel.
For you greenies, it also reduces toxic exhaust emissions by 12%.

Albert Biermann, head of research and development at Hyundai Motor Group, told The Corner in a media release: “The development of CVVD is a good example how Hyundai is strengthening its powertrain technology.”
Here’s how it’s said to work…
”Until now,” Hyundai explains, ”an internal combustion engine’s performance and efficiency have been governed by variable valve-control adjusting the timing of valve opening/closing. Engine power is produced through the injection-intake-compression-expansion-exhaust cycle.
READ MORE Hyundai and Kia features on Carman’s Corner
”Previous variable valve-control could not regulate the duration of the opening as the valve’s closing timing was subordinate to opening timing and could not respond to various driving situations. CVVD determines how long a valve remains open.”
On the road at a modest constant speed CVVD opens the intake valve from the middle to the end of the compression stroke to benefit fuel economy by reducing the resistance caused by compression. At high speed, the intake valve is closed at the beginning of the compression stroke to maximize the amount of air used for the explosion, so enhancing torque to improve acceleration.
Smartstream G1.6 T-GDi Engine
Unveiled alongside the CVVD technology is a new Smartstream G1.6 T-GDi engine, a 135kW, four-cylinder, turbo-petrol unit and the first to have the group’s CVVD tech. It also has low-pressure exhaust recirculation to burn any remaining fuel in the gases.
The engine also has a thermal management system that quickly heats or cools the engine to an optimal temperature and a direct injection system that achieves 350bar, way above the 250bar of the previous T-GDi engine.
WATCH A VIDEO of the new engine in operation here
In addition, engine friction has been cut by 34% thanks to what the group describes as ”low-friction moving parts”.
The Smartstream G1.6 T-GDi engine will be mounted in the Hyundai Sonata Turbo which will arrive in South Africa later in 2019 – the first of a series of new Hyundai and Kia vehicles to have the engine.