Volvo?s Twin Engine plug-in hybrid branding might not be completely accurate?so far, each iteration of the theme has incorporated only a single engine, as well as an attendant electric motor or two?but the newest version is quite novel nonetheless. While the ?T8? Twin Engine setup in the XC90 SUV carries two electric motors, one fitted between the engine and the transmission and another powering the rear axle, the ?T5? variant destined for Volvo?s new compact 40-series cars has only one electric motor aiding a turbocharged three-cylinder engine in a crafty way.

As is the case for most hybrids, the transmission is among the most critical components in Volvo’s setup. The seven-speed dual-clutch automatic is bolted to the end of Volvo’s all-new turbocharged 1.5-liter three-cylinder engine, just as it would be in a non-hybrid application, and its output shaft turns a differential and two unequal-length driveshafts that spin the front wheels. So where’s the electric motor" Unlike pretty much every other front-wheel-drive, transverse-engine hybrid out there, the Twin Engine T5 system hangs the electric motor off the top of the transmission?it’s mounted externally?and delivers its torque to the transmission’s output shaft via one of the dual-clutch’s two input shafts.
In case we’ve lost a few of you, here’s a quick refresher on dual-clutch automatics, so that you have an idea of what we’re talking about when desc...