The "37" means that for 2009, Infiniti's smallest sedan has played catch-up with its coupe counterpart and has ditched its 3.5-liter engine for a more technological 3.7-liter producing 328 hp and benefiting from a wider powerband thanks to Variable Valve Event and Lift. Unlike most systems that only alter timing, VVEL uses both hydraulically-controlled variable valve timing and electronically controlled variable valve lift on the intake side, which improves performance, response, emissions, and fuel efficiency. A relatively low increase of 22 hp might not seem worth all the trouble, but overall, the engine doesn't feel as coarse as the outgoing unit, a long-running complaint of Infiniti's otherwise brilliant VQ-series. The power increase is also noticeable throughout the rev range, not just at its peak, and EPA test figures should be up one mpg over the previous G sedan, thanks to a new seven-speed automatic transmission.

The sport-packed G37 not only gets a new wheel design, but also the coupe's bigger brakes. Squeezed by four-piston calipers up front and two-potters in the back, the rotors measure 14.0 inches and 13.8 inches, respectively.