ROADSTER TO RELISH
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by Wynter Murdoch
Nissan’s recently released 370Z Roadster is likely to be, for many, the epitome of a sports car that’s a lot more seductive than tin-top rivals.
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When developing the 370Z, Nissan’s California-based design team is said to have worked separately from the outset on two different models – a coupé and a convertible. That’s one of the reasons why, from some angles, the lines of the newly introduced Roadster look quite different to those of its tin-top counterpart – the obvious disparity apparent in the flow of the roofline from A-pillars to the tip of the boot.
While the convertible lacks the smooth, clean, fastback styled silhouette of its sibling, it nevertheless manages to appear aerodynamically adept – and, with the folding soft-top neatly tucked up at the rear under a hard tonneau cover, perhaps for many it will be representative of a sports car that’s a lot more seductive than its counterpart.
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What’s important to note, however, is that the design teams went beyond appearance in developing the inherent qualities of the derivatives – Nissan’s spokesmen making some strong claims for the Roadster’s revised chassis and underpinnings, which they say have made the car leaner, lighter and stiffer than its predecessor, the 350Z Roadster.
Significant changes are said to encompass a lowering by 15mm of engine and transmission mountings, thus dropping the centre of gravity; increased torsional rigidity both front and rear; a widened track and a chassis length truncated by 100mm.
Translated to the road, this means better dynamic behaviour and more agility, the enhancements, for me, embodied in the car’s high speed behaviour in a tight left hand bend on rutted tarmac. Where lesser models are likely to have lost traction and spun in similar circumstances, the 370Z Roadster remained composed, with no scuttle shake or inordinate cowling flex apparent from the driver’s seat, the overwhelming sensation from the cockpit being the sure feel of considerable grip at the wheels, the nose of the car answering with laser-like accuracy all commands from the helm.
The suspension layout follows Nissan’s tested formula of double wishbones at the front and a multi-link rear end, but both systems are described as having been upgraded extensively – stronger than before and offering greater lateral stiffness to minimise the effects of camber change.
Forged aluminium alloy links at the front are lighter than those used previously, while the revised sub-frame – a high vacuum die-cast alloy cradle – delivers similar weight savings. Other changes at the front include reinforced steering arms and bigger front hub bearings while the hollow anti-roll bar is not only lighter, but also significantly stiffer.
Weight savings at the rear come through lighter aluminium alloy castings, but the major changes are to the increased stiffness of links and the cradle itself. As at the front, larger hub bearings and a more robust yet lighter anti-roll bar complete the package. High response shock absorbers help to provide a compliant ride.
Overall weight has been reduced by 62kg compared with that of the 350Z Roadster, despite the new car having more standard equipment. Contributing factors to the weight savings include the use of aluminium for doors and bonnet, as well as the fact that the model’s chassis architecture needs less reinforcement than its predecessors. |
| The drivetrain has a lot of horsepower to deal with. Like the coupé, the Roadster is powered by an aluminum-block 3,7-litre V6 which features Variable Valve Event and Lift (VVE-L), Nissan’s compact, responsive and comparatively mechanically simple intake system – it has only 13 parts – which does away with conventional valve springs. |
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The engine is mated to a choice of six-speed manual gearbox – which features synchro-rev control to match road speed with engine revs when changing down – or a seven-speed automatic. Power is rated at 245kW at 7 000 revs/min, with maximum torque of 363Nm produced at the 5 200 revs/min mark.
While the Roadster is a performance car that enthusiastic drivers will relish, it is also sublime as a cruiser. Though the chassis setup is sporting, ride quality suffers little thanks to just enough compliance in the underpinnings to smooth out all but the most prominent humps, bumps and ridges.
At speeds of about 120km/h, the cabin remains quiet and comfortable even with the top down, due in part to the car’s fixed-glass wind deflector and custom-designed seats that help to prevent air from blowing back into the cabin. With the roof up, double layers of insulating material do a commendable job of keeping out wind, road and exhaust noise.
Off the line the manual derivative is a little quicker to 100km/h than the auto version – 5,5 seconds as opposed to 5,8 seconds, according to Nissan’s claims. Top speed for both models is electronically limited to 250km/h.
In terms of styling, design cues already seen on the coupé have transferred to the Roadster. They include distinctive boomerang LED rear and arrowhead front lights, while familiar features such as vertical door handles, twin tail pipes and Z badges in the side repeaters are also present.
The driver-focused cabin also boasts many features now synonymous with the Z, such as an engine stop/start button, floor hinged throttle pedal, wide and soft pads mounted on the central transmission tunnel to protect occupants’ knees, a centrally placed tachometer and three separate hooded dials – including an oil temperature gauge – mounted centrally on the top of the dashboard and angled towards the driver.
With regard to the roof, a fully automatic hydraulic system has replaced the semi-automatic electric motor based raising or lowering mechanism of the predecessor, either task completed in 20 seconds at the press of a button.
“A lot of time, effort and engineering expertise were invested in the development of the roof. We wanted to make sure that it functioned as well as it looked. It operates very quickly and smoothly,” says a Nissan spokesman.
Hydraulic speed sensitive rack and pinion steering has also been revised to provide more communicative feedback and better response around the dead ahead position, while braking performance has been enhanced with larger diameter ventilated discs front and rear and the adoption of a variable ratio brake pedal to offer more movement for easier control at low speeds, but a firmer action when high G-forces are generated.
The new system is said to have greater resistance to fade under sustained usage while new pad material helps reduce stopping distances, at the same time curtailing brake dust and reducing brake squeal.
A full complement of electronic safety aids includes the latest generation ABS with Electronic Brakeforce Distribution (EBD) and Brake Assist (BA).
Standard equipment levels include climate control, an auto-dimming rear view mirror, automatic interior temperature control with in-cabin micro-filler, power heated leather seats with slide resistant cloth inserts, a viscous limited slip differential and an energy absorbing steering column.
The manual version sells for R543 000, while the auto derivative is priced about R18 000 higher. The cost includes a three-year/90 000km service plan and three-year /100 000km warranty.
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| SPECIFICATIONS |
| ENGINE |
| Type: |
V6 |
| Displacement: |
3 696cc |
| Power: |
245kW @ 7 000 revs/min |
| Torque: |
363Nm @ 5 200 revs/min |
| PERFORMANCE |
| 0-100km/h: |
5,5 / 5,8 seconds |
| Top speed : |
250km/h (limited) |
| TRANSMISSION |
| Type: |
Six-speed manual with synchro rev control / Seven-speed auto with manual sequential shift |
| STEERING |
| Type: |
Rack and pinion, power assisted, speed sensitive |
| Turns lock to lock : |
2,5 |
| SUSPENSION |
| Front: |
Independent. Double wishbone multi-link aluminium-alloy with stabiliser and strut bar |
| Rear: |
Independent. Multi-link aluminium-alloy with sub-frame, stabiliser and strut bar |
| WHEELS & TYRES |
| Wheels: |
19-inch alloy |
| Tyres f/r: |
245/40R19 94W / 275/35R19 96W |
| FUEL |
| Tank capacity: |
72 litres |
| Consumption (l/100km) : |
11,2 / 10,9 combined cycle |
| DIMENSIONS |
| Length: |
4 250mm |
| Width: |
1 845mm |
| Height: |
1 325mm |
| Wheelbase: |
2 550mm |
| Track f/r: |
1 550mm / 1 595mm |
| PRICE |
| Manual: |
R543 000 |
| Auto: |
R561 000 |
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