Cylinder deactivation helps automakers squeeze better fuel economy out of larger engines by cutting off some cylinders under light loads. Systems in production now typically deactivate no more than half of an engine’s cylinders, but three companies are collaborating on a new one that takes a more aggressive approach.

Called Dynamic Skip Fire (DSF), the prototype system allows a V-8 engine to run on as few as two cylinders while cruising at highway speeds. It’s based on an algorithm created by Silicon Valley startup Tula Technologies, and is being developed in partnership with General Motors Company [NYSE:GM] and Delphi