GMs Advanced Cylinder Deactivation Could Add 15% to EPA Results

It is called Dynamic Skip Fire.

Wayne Gerdes - CleanMPG - Jan. 6, 2015



Another release from GM regarding cylinder deactivation but with an interesting twist.



GM Ventures 2012 equity investment in Silicon Valley-based startup Tula Technology should result in a new displacement on demand fuel saving technology that could be deployed in future gasoline engine-powered GM vehicles.



Currently, GM’s Active Fuel Management (AFM) or variable displacement on demand conserves fuel during low power demands by switching off an even number of cylinders until a higher load is required. It does this by closing both the intake and exhaust valves for those cylinders being shut down. The current technology as implemented improves fuel economy by 6 to 8 percent.



The Next Generation of AFM



Tula technology is called Dynamic Skip Fire (DSF) that integrates digital signal processing with powertrain controls to create a software-based approach to the most of the fuel consumed across a wider range of driving conditions.



Instead of relying on GMs current fixed cylinder deactivation, Tula’s DSF technology makes dynamic firing decisions for individual cylinders to deliver the required engine torque for all vehicle speeds and loads. The hard part of cylinder deactivation is the high NVH induced and Tula’s solution supposedly cures that too.



Independent testing shows that the application of DSF technology can improve fuel efficiency in a multi-cylinder engine (4/6/8 cylinders) by as much as 15 percent when compared to a vehicle equipped with an engine that does not have cylinder deactivation.



Bring it on GM, bring it on.

GMs Advanced Cylinder Deactivation Could Add 15% to EPA Results