Nissan Motor Co. Ltd. 3.5L DOHC V-6
By Bill Visnic WardsAuto.com, Dec 20, 2006 9:02 AM

We wondered where Nissan Motor Co. Ltd. possibly could go with its VQ-series 3.5L DOHC V-6 after winning a 10 Best Engines award for a dozen consecutive years. After all, most contemporary engine families don’t last this long, much less last this long at the top.

So where is Nissan going? To the podium for its 13th award.

The company’s engineers apparently don’t intend to relinquish the VQ’s now-legendary status as the definitive V-6 benchmark because this year, the fourth generation of the VQ is 80% new, flaunting revised design features that address the one development aspect in which the VQ had been slipping – refinement – and brewed in a fresh new level of performance, just to be certain everybody knows they’re serious.

In recent 10 Best Engines competitions, Ward’s editors have been straightforward about the VQ’s benchmark role: It’s tough to rag on a legend, but ever since the ’02 model year, when Nissan bored the sweet original 3L VQ to a brawnier 3.5L, we’ve noted an erosion of refinement.

Noise, vibration and harshness levels had been sacrificed at the altar of increased horsepower and torque.

The modular DOHC V-6 that launched in 1995 in the U.S. at 3L and 190 hp gradually had grown to 3.5L and as much as 298 hp – a 50%-plus hike in power from just a 17% increase in size.

Fourth-generation Nissan 3.5L DOHC V-6 80% new.

But for the fourth-gen ’07 variant, the VQ35HR, there’s a critical new structural ladder frame, an enlarged crankpin and crank journal diameter, a new cylinder-head design, a trick new asymmetric piston skirt and longer connecting rods, in addition to a raft of friction-reducing updates.

The engineers out there easily will assemble the puzzle to see improved NVH was a prime target.

It worked. The VQ has regained much of its hallowed silkiness.

“Once again, it’s easy to forget to upshift, it revs so smoothly,” Editor Drew Winter says.

But all that refinement attention bore gifts even better than those best appreciated by the J.D. Power quality fanatics. The “HR” designation for this latest-generation VQ stands for “high revolution,” meaning there are more revs available from an engine that always preferred the high-altitude section of the tach to begin with.

The VQ35HR now offers a luscious 7,500-rpm redline (up from 7,000 rpm with the manual transmission for the old VQ) and revs so passionately that a gearshift feels unnecessary before 6,000 rpm.

A 6,800-rpm power peak would be a warning sign in less religiously detailed engines. But for the new VQ, that region of the tach is fully and invitingly exploitable.

All those revs mean extra power, too, and the HR variant of the VQ (a fourth-gen VQ35DE with fewer of the high-rev ministrations will be fitted for several models) loads up with 306 hp and 268 lb.-ft. (363 Nm) of torque – power that matches the class-leading Lexus IS 350’s 3.5L DOHC V-6, but lags it slightly in torque.

Nissan engineers say they developed the high-rev variant of the 3.5L DOHC V-6 to be a more “emotional” experience, and we’re down with that, too.

Anytime you can spin a V-6 to 7,500 rpm, get more power and refinement and bask in magnificent new sounds specifically targeted for the HR, there’s nothing to do but once again award the champion its hard-earned belt.

bvisnic@wardsauto.com