Question: What should a car company do with a nameplate that burst on the scene just four years ago and has proven itself a success?

Answer: Keep the pedal to the metal.

That's just what Infiniti is doing by freshening its G35 sedan for the 2007 model year.

While the 2007 G35 sedan isn't completely redesigned from the ground up, the modifications Infiniti has made add up to more than just a midcycle enhancement. The most notable changes include a completely new body and an all-new interior. Infiniti has also chosen to upgrade the G35 in its two strongest areas: chassis and engine. While the chassis retains the same architecture, some revisions have been made to make it stiffer, and the 3.5-liter V6, which propelled 2006 models from 0 to 60 mph in 6.0 seconds, has been reworked.

An Award-Winning History
Infiniti took a big chance when it introduced the G35 in March 2002 as a 2003 model, but a combination of fine execution and deft planning yielded a winner. By choosing to go with a longitudinal front-engine, rear-drive, sport sedan, Infiniti tacitly stated it was willing to take on the BMW 3-Series, an entry-luxury icon.

The ploy worked, and the G35 launched with rave reviews. It was named one of Car & Driver magazine's 10 Best for 2003 and 2004, it earned the Motor Trend 2003 Car of the Year honors, and it's been a Consumer Guide Recommended pick since it hit dealership floors. All that, however, doesn't mean it can't get any better.

G35's interior is available in two different trims; aluminum (top) or African Rosewood (bottom).

New Interior and Exterior
The 2007 G35 sedan looks much like its predecessor, but every body panel is new. Notable differences include the grille, which changed from flat horizontal bars to "twisted horizontal blades inspired by traditional Japanese swords," according to Infiniti, a more sculpted hood, three lower front air intakes instead of two (Sport models get yet another design), redesigned head and tail lights, new wheel designs, and more-pronounced rear haunches.

If reviewers had one complaint about the 2003-06 G35, it was the interior. Infiniti has started fresh for the 2007 model, aiming for "modern warmth." The instrument panel has white and violet gauges, with a red center readout for drive computer information. The biggest change is the center stack, which features a standard seven-inch display (with or without the optional navigation system), an analog clock, an angled control panel for the navigation system/information center, and African Rosewood or aluminum trim. The aluminum is textured to look like Washi, a handmade Japanese paper. It and the Rosewood trim are also used across the instrument panel and on the door panels.

Whether or not the navigation system is ordered, the radio and climate controls are separate. Their readouts now appear on the seven-inch screen, instead of high up on the dashboard like the previous model. Buyers who opt for the nav system get a standard 9.5-gigabyte hard drive for music file storage, and they can also order XM NavTraffic, which gives real-time traffic information.

Leather upholstery and keyless access/ignition are standard. The Sport model with automatic transmission offers magnesium paddle shifters. Other options include a rearview monitor, upgraded Bose audio, adaptive radar cruise control, and a wireless cell phone link.

A Good Engine Made Better

The Nissan 3.5-liter V6, known internally as VQ, is widely respected as one of the best engines on the market. An all aluminum 24-valve, dual-overhead-cam design, it was offered in two states of tune in the 2006 G35. When teamed with an automatic transmission, it made 280 horsepower and 270 pound-feet of torque. With the manual transmission, it made 298 hp and 260 lb-ft of torque.

Infiniti has substantially revamped VQ for its fourth generation, replacing or revising 80 percent of the parts, including a new stiffer block. Along the way, Infiniti raised the compression ratio from 10.3:1 to 10.6:1, improved cooling, adopted true dual exhaust with equal length headers, moved the redline from 6600 rpm to 7500 rpm, and added electromagnetic variable timing for the exhaust valves (hydraulic VVT for the intake valves is carried over). The result is 306 hp and 268 lb-ft of torque, a 0-60 mph in the low-to-mid five-second range, and EPA fuel-economy numbers of 19/27 mpg with the manual and 19/26 mpg with the automatic (both up slightly from '06). In addition, Infiniti has introduced a symmetric twin ram air intake system that reduces airflow resistance and adds three horsepower at 60 mph.

All that power is fed through a six-speed manual or five-speed automatic transmission with manual shift gate. While competitors are going to six and even seven speeds for their automatics, the G35 sticks with five, though a company insider said a seven-speed is in the works. The automatic is modified from that last version, however, thanks to the addition of Downshift Rev Matching. The transmission is programmed to blip the throttle on downshifts to match revs and thus reduce shift shock.

2007 Infiniti G35 sedan

Chassis Tweaks

The key to any sporty car is a rigid chassis. Infiniti developed a fine rear-wheel drive platform for the 2003-06 G35, and has improved it for 2007. The '07 G35 shares its FM platform with the Infiniti M. FM stands for front midship, which means the engine is located behind the front axle instead of over it. While the platform is basically the same physically as it was for the original G, the track (the distance between the wheels on an axle) is wider by 0.7 inch up front and 0.9 inch at the rear. Thanks to new structural pieces in the engine compartment and 16 percent more body spot welds, the chassis has 36 percent more torsional rigidity.

The front suspension geometry is also changed. Infiniti has switched from two lower links and a wishbone on top to double wishbones. The final change is optional. For the first time, Sport buyers get staggered tire sizes (225/50R18 up front and 245/45R18 out back). These tires are optional on other models.

Infiniti also incorporated its four-wheel active steer system, which has been available on the Infiniti M and G35 coupe but never on the G35 sedan. Based on steering input and vehicle speed, the system adjusts rear wheel toe up to one degree to improve handling. Cars equipped with Rear Active Steer get stiffer shocks at all four corners that help handling but hurt the ride. The front steering is also speed sensitive, ranging in ratio from 12.0:1 (for quick low-speed turns) to 18.5.1 (for steady highway cruising).

Like its predecessor, the 2007 G35 offers an all-wheel drive model called G35x. The Advanced Total Traction Engineering System for All Electronic Torque Split (ATTESA E-TS), as Infiniti efficiently calls it, actively distributes torque between the front and rear tires depending on conditions. In normal mode, it runs with a rear-drive bias, but as much as 100 percent of the torque can be shifted to the front wheels in low traction situations.

November Reign

Set for release in November, the 2007 Infiniti G35 sedan will be offered in five models: base G35, G35 Journey, G35x AWD, G35 Sport, and G35 Sport 6MT. Sport models have standard limited slip differential and sport suspension, and offer Rear Active Steer as an option. Pricing wasn't available in time for this report, but Infiniti says it should be in line with the last generation model. That means it should start in the low $30,000 range, the same range as the BMW 328i and Lexus IS 250, both of which offer less power.

With its improved interior, an even stiffer chassis, and reasonable prices, the 2007 G35 should put more pressure on competitors like the BMW 3-Series. But even if it doesn't, Infiniti feels it will remain successful in the growing near-luxury market.

Infiniti says the entry-luxury market is on the rise. According to the automaker, the segment saw some 448,000 registrations in 2001. That number grew to more than 607,000 in 2005, and Infiniti expects it to approach 760,000 units by 2011. Obviously, Infiniti expects the G35 to benefit from that growth.