In the race to field energy-efficient vehicles, don’t count out internal combustion technology just yet. GM recently debuted its homogeneous-charge-compression-ignition (HCCI) system in two drivable ...

In the interest of making sure we all know they've got a mapped strategy for powertrain technology, GM is taking its message on the road. Recently, we got the chance to talk to a few of GM's experts ...

A.Here's a pressure-volume diagram for a combustion engine. Although rough, it is an approximation of the so-called air-standard cycle. '' Point (a) is at atmospheric pressure, after which the air is ...