Has Nissan designed a really smart coupe right with the
Infiniti G37 Coupe, which is getting near a sports car in performance? They have certainly tried hard, enlarging the 3.5 liter V-6 from the 350Z to 3.7 liters, and pushing power up to 330 bhp. Also, the car looks pretty slick in coupe form. There is also a convertible.
With a few notable exceptions such as the 350 Z, Nissan styling has always been lacklustre , but this is all changing now. The new Infiniti G37 certainly looks the part, but retains a grille that is similar to other Infiniti models – Nissan has decided that if the Europeans retain their grilles as good trade marks, so their's should do the same trick for Infiniti.
Low Cd of 0.29
Overall, the G37 is a pretty slick looking job, but leaning towards the cruiser rather that the sports car in its lines, but pleasing nonetheless. Also, the body is efficient – the Cd is only 0.29 – as good as you get anywhere. There is claimed to be zero front lift, and you can have a rear spoiler if you want.
The car is built on a conventional steel platform, although there is quite a lot of high-strength steel in the body, which reduces weight. The hood is aluminum. The car weighs in at 3,616 lb (1,641 kg) which is not bad for a car of this size – virtually the same as the Audi S5, which has a larger engine and four-wheel drive – but could be better.
Also, the engine is perhaps a little too far forward, so the weight distribution is 54 per cent front to 46 per cent rear, which is a touch too much weight on the front for the best handling and traction.
Competes with the Audi A5 and S5
Direct competitors for the G37 are the Audi A5 and Hyundai Genesis Coupe. Nissan needed to make sure that the G37 was larger and more comfortable than the 350Z, and would appeal to different people – the last thing they want is for people to choose the G37 instead of a 350Z or vice versa. In fact, the G37 has an 8 inch (200 mm) longer wheelbase, giving good rear seat space, and is 13 inches (340 mm) longer overall. That, coupled with the different styling is enough to differentiate the two cars.
Variable valve lift and timing
Under the hood, the 3.7 liter engine, now with variable valve lift and timing, rather than the variable timing achieved by rotating the camshafts a few degrees relative to the crankshaft as needed. This is following a trend pioneered by Honda some 17 years ago, but since copied by many car makers including Porsche, Audi and Toyota.
Each uses a slightly different mechanism to give short, low lift at low speeds, and high, long lift at high speeds – so you get the cams from an ordinary engine at low speed, and a really sporty engine at high speed. This will eventually become universal on all except the base models.
Complex variable valve timing and lift mechanism
However, Nissan has gone further and developed a complicated system which can vary the valve lift and timing continuously. At low speeds and load the engine power is determined by the valve opening lift and period, thus reducing losses and improving fuel consumption. The system involves the use of an electronically controlled motor and ball screw which actuates an eccentric, and various levers.
In the G37, this engine is tuned for top-end power, with 330 bhp being delivered at 7,000 rpm, and maximum torque coming in at 5,200 rpm, suggesting that despite the fancy valve gear, there is not much power low down.
Of course, this is an all-aluminum engine with four valves per cylinder, and it is going to provide the G37 with plenty of power, and high revs – the red line is at 7,500 rpm, the same as the latest version of the Z350. As the Z350 has been upgraded, using the same tall block as the G37, Nissan reckons 3.5 liters is enough there.
As standard there is a six-speed manual box, but you can also have a five-speed automatic, with paddle-controlled manual shifting. On G37 Coupe Journey with Sport Package you can have a limited slip diff in the form of a viscous coupling – a very good and simple solution.
Double wishbone suspension
Nissan has been using double wishbone front and multi-link rear suspension for some time, and this is the set-up on the G37 To save weight most of the links are aluminum. Also, you get four-wheel steering which is of dubious benefit in that it does not give the driver the true signals of what is happening. It also seems a bit redundant now that stability systems are in use.
There is ABS and brake distribution control, of course, and also stability control. As you would expect, 18 x 8-inch aluminum alloy wheels are standard, with 225/50VR18 tires. There is an option of 19-inch wheels with 225/45WR19 front tires and 245/40WR19 rear tires to give more traction.
Overall,the Infiniti G37 looks a worthwhile addition to the sporty coupe market, with good looks and performance.
