Hi all,
I found a BSFC map of the gasoline engine form the Opel Ampera/Chevrolet Volt. Its a 1398ccm four cylinder(bore 73,4mm, stroke 82,6mm, compresion ratio 10,5).
The power output is 63kW/4800rpm, 130Nm/4250rpm. It comes from GM family 0, generation 3 engines.
The maps show BSFC + generator efficiency and lines of GM strategy for battery charging. The engine is used as a range extender for the EV.