Electric powertrains are all the rage these days, but the evolution of the internal combustion engine hasn’t slowed. In fact, new changes are coming faster than ever.

Consider, for example, this short list of recent engine innovations: a turbocharged engine with no cams; a new diesel with the world’s lowest compression ratio; a four-cylinder engine with a variable compression ratio; and the world’s first gasoline-burner to employ compression ignition.

Here, we’ve collected photos of engines offering some of the latest innovations in powertrain technology. From intelligent truck engines to tiny turbocharged models, we offer a potpourri of some of the highlights from the past few years. Flip through the following slides to see the best.

(Image source: Mazda Motor Corp.)