- Oct 9, 1999
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http://www.automobilemag.com/multimedia..._gallery/0703_2008_infiniti_g37_coupe/
First thing's first - just as you'd expect, the higher number in the G37's name denotes a larger displacement engine. The 2007 model's VQ35 3.5-liter has been stroked to 3.7 liters. The new engine, dubbed VQ37VHR, now has an 86-mm stroke (up from 81.4 mm) and a compression ratio that is, at 11.0:1, four-tenths of a point higher.
The biggest news about the engine, however, is that it is the world's first application of Nissan's VVEL (Variable Valve Event and Lift) technology. Like BMW's Valvetronic, VVEL eliminates the need for a conventional throttle butterfly, controlling engine output by continually and steplessly varying valve lift and timing. The V-6 retains a conventional throttle butterfly, but it's used for emissions-related purposes only, according to Nissan.
By having infinite control over both valve lift and timing, Nissan was able to flatten the VQ's torque curve at both the bottom and top of the rpm range. The result is that while the 3.7-liter's 270 lb-ft peak torque is only 2 lb-ft higher than the 3.5-liter's, the curve shows improvements of about six percent down low and four percent up high.
The increase in high-rpm torque results, of course, in more horsepower. The G37 is preliminarily rated at 330 horsepower. And as a result of VVEL, it should beat the 3.5-liter's EPA fuel economy ratings. Now that's progress.
Nissan says that, compared with BMW's Valvetronic, VVEL is 32% quicker to respond, 20% smaller, and uses 52% less parts per cylinder. It also allows the engine to rev higher - the 3.7-liter is redlined at 7,500rpm.