Nissan Motor Co. Ltd.: 3.7L DOHC V-6

Special Report

Ward’s 10 Best Engines

By now, Nissan Motor Co. Ltd.’s all-conquering VQ V-6 architecture needs no introduction.

The 3.7L variant’s 2008 10 Best Engines award marks the 14th consecutive win for the VQ, and it is the only engine to win every year of the competition’s history.

The VQ “brand” was established in 1995 on the pillars of landmark refinement and ultra-low noise, vibration and harshness levels.

Like many rivals, however, Nissan has not resisted the temptation to increase displacement, and over the years it grew into three distinct iterations: the original and oh-so-smooth 3.0L, the 3.5L introduced in 2002 (and still powering the majority of models from Nissan and its premium Infiniti brand) and the new 3.7L DOHC V-6 (VQ37VHR), which wins the 10 Best Engines award for 2008 and for now is available exclusively in the ’08 Infiniti G37 Coupe.

In the quest for punchier power and torque numbers, the move to 3.5L was, to our senses, a tradeoff that peeled back on the VQ’s signature refinement. But when the company’s engineers unleashed the HR (High Rev) generation last year, many of the design changes – a structural ladder frame in the block, larger crank journals and asymmetric piston skirts, to name a few – had the tertiary effect of improving NVH while enabling higher, more satisfying engine speeds.

Now the stroked 3.7L variant of the VQ’s HR design enjoys the same, only moreso. Our favorite: the sweet sting of 330 hp, a power improvement of almost 10% compared with the VQ35HR.

A little perspective helps, too. The latest VQ V-6’s 330 hp is 30 horses stronger than Ford Motor Co.’s standard 4.6L Mustang V-8.

A prime goal was permitting engine speeds even higher than the 3.5L HR variant. Here, Nissan’s octane-crazed engineers didn’t mess around. The hair-raising new redline of 7,500 rpm is effortlessly and smartly accessed with almost no adverse auditory or tactile sensations.

Nissan says about 35% of the parts are unique to the 3.7L VQ, and the major new addition is the electronically adjusted variable valve lift (Variable Valve Event and Lift), imparting a “throttleless” effect not unlike BMW AG’s Valvetronic, which also markedly reduces pumping losses by essentially throttling the engine with the intake valves.

Even with the efficiency claims for VVEL, we believe fuel economy, at 17 mpg (13.8 L/100 km) in the city and 26 mpg (9 L/100 km) on the highway is hardly encouraging, and is one of our few complaints about the 3.7L DOHC V-6.

But this latest 3.7L variant of Nissan’s special VQ V-6 may be the best in 14 years and is a magnificently focused engineering effort.

Ward’s 10 Best Engines is copyright Penton Media Inc. Commercial references to the program and/or awards are prohibited without prior permission of Ward’s Automotive Group.