Nissan claims that, compared with BMW's Valvetronic, VVEL is 32 percent quicker to respond, 20 percent smaller, and uses 52 percent fewer parts per cylinder. It also allows the engine to rev higher--the 3.7-liter's maximum engine speed is 7500 rpm.
The six-speed manual transmission is a revised version of the one in the current G35 sedan. Nissan engineers worked to reduce NVH and have also modified the clutch engagement. Both changes will be shared with the sedan starting in 2008.
The car we drove, however, was equipped with a five-speed automatic. Even with that transmission, we noticed no throttle lag due to the VVEL. Indeed, the throttle was precise enough to help us do exactly what the G coupe loves to do best--fantastic power slides. All manual-transmission cars (as well as automatic-equipped sport package cars) will have limited-slip differentials.
The G37 has a new steering gear and, like the sedan, will be offered with four-wheel active steering. The car we drove had traditional two-wheel steering, although it did have the quicker steering ratio that's part of the sport package.
With that said, the steering in the pre-production car wasn't as communicative as BMW's system. It is, however, a vast improvement over the previous coupe's steering, which transmitted as much vibration as it did road feel. And the production version could be even better.
The second-generation FM platform is not only 36 percent stiffer than the previous one, it also has a wider track and a lower center of gravity. Compared with the outgoing coupe, the G37's suspension has higher spring rates, larger antiroll bars, and stiffer damping. Eighteen-inch wheels are standard, and nineteens are optional. Behind those wheels hide the largest rotors in the segment: 14.0 inches at the front and 13.8 inches at the rear, straddled by four-piston aluminum front calipers and two-piston rears.
On the track, the G37's neutral chassis balance and tight body control gave us a perma-grin. In fact, the Infiniti's body motions were better controlled than those of the BMW 335i (which also was equipped with a sport package). The G37's limited-slip rear differential prevented the frustrating inside wheel spin that plagued the open-diff-equipped BMW, and the suspension heaved less over the big bumps that were strategically placed on the track.
On the brief straights, however, the G37 didn't feel quite as fast as the 335i, nor did its V-6 sound quite as melodic as the BMW's twin-turbo straight six. As with the previous Gs, the five-speed automatic does a pretty good job of smoothing out some of the V-6's coarseness inside the cabin, but the ratios are too widely spaced.
Nonetheless, we came away very impressed. The G37 was a lot of fun to thrash over the bumps, curves, and dips at Nissan's proving ground. We would like to see the G37 move up to a six-speed automatic, and we're looking forward to sampling the revised manual transmission. Infiniti engineers caution that the early mule car was only 90 to 95 percent complete, with final tuning still underway. Even so, when the G37 arrives this fall, it could very well topple the BMW from its perch at the top of the segment.