Expecting to hit the engine production lines next year the new cylinder deactivation technology can cut 15% off the CO2 emissions off larger engines like a V8 or V12 and up to 8% on smaller four engines.
Delphi the automotive parts supplier have teamed up with Tula an automotive tech firm to create Dynamic Skip Fire or DSF, The system is the industry’s very first dynamic cylinder deactivation program.
The biggest savings in CO2 comes from the big engines like a V8 with up to 15% shaved off the grams per kilometre. It is claimed to have the ability to make small turbocharged four cylinder petrol engines as fuel efficient as their diesel counterparts.
How does this new Dynamic Skip Fire work?
The innovative new system DSF works by deciding whether or not to fire or skip a cylinder as it comes round to the combustion stage. When a cylinder is skipped, both the exhaust and intake valves are held shut by the Delphi hardware and the spark plug is not activated. There is no spark and can only be used on spark ignition engines like petrol, leaving compression ignition diesel engines excluded. The DSF continues to dynamically adjust and can make up to 32,000 decisions a minute depending on all the inputs from the engine and driver.
Tula President and CEO Scott Bailey said “Every time a cylinder is ready to be fired, the system makes a dynamic decision, do we fire this cylinder or do we drive this cylinder for torque reasons?" He also added “We don’t look at running fixed patterns (like conventional cylinder deactivation systems), so we can run anywhere from zero cylinders to 100% of the available cylinders, with any firing density between them,"
The system is up and running on their demonstrator Volkswagen Jetta featuring a 1.8 litre, four cylinder, turbocharged engine. They have plans further down the line to introduce a working 48V hybrid system and are actively working on the project with two manufacturers.
John Kirwan, chief engineer of advanced R&D at Delphi Powertrain, said that the biggest savings can be made in larger capacity engines like V8s and V12s, but that the first models to use the system will have smaller turbocharged units. "We can't say what model it'll be fitted to first, but we can say that a large, global manufacturer will be the first to use it in a car from 2018,"