Review: Infiniti Y51 Q70 (2014-19)

Review: Infiniti Y51 Q70 (2014-15)

Overview

Released in January 2014, the Infiniti Y51 Series I (Y51.I) Q70 was an executive sedan. Manufactured in Tochigi Japan, the rear-wheel drive Q70 was available with three drivetrains: a 3.7-litre V6 petrol engine, a 3.0-litre turbo-diesel engine or a hybrid drivetrain with a 3.5-litre V6 petrol engine and an electric motor. The Q70 was initially released in Australia as the M sedan , but was renamed for 2014.

Powertrains

For the conventional powertrains,

• the 3.7-litre VQ37VHR V6 petrol engine had an aluminium block and heads, double overhead camshafts, four valves per cylinder, a compression ratio of 11.0:1 and Nissan’s VVEL (‘Variable Valve Event and Lift’) system which combined hydraulic-controlled variable valve timing and electronically-controlled variable valve lift on the intake side; and,
• the 3.0-litre V9X turbo-diesel V6 engine had a compacted graphite iron (CGI) block, aluminium cylinder heads, Bosch common-rail injection (operating at 1800 bar), intercooler, double overhead camshafts, four valves per cylinder, exhaust gas recirculation and a compression ratio of 16.01:1.

The Q70 Hybrid combined Nissan’s VQ35HR engine – operating on an Atkinson cycle – with a 50 kW electric motor which was installed in parallel between the engine and transmission. Electrical energy was stored in a 1.3 kWh lithium-ion battery pack which was installed upright behind the rear seats; the battery pack was expected to have a service life of ten years. The Q70 Hybrid was fitted with an ‘Electric Driven Intelligent Brake’ system which used the electric drive motor to operate the brake cylinders; braking force was also maintained while the hydraulic pressure of the friction brake was also controlled to maximise energy regeneration.

Other innovations for the Q70 Hybrid included an electro-hydraulic steering system with ‘on-demand’ assistance, which sought to provide the feel of a hydraulic system with the fuel efficiency of an electric system, and twin clutches which enabled the V6 engine to be decoupled when the car was in electric drive and power regeneration mode. The Q70 Hybrid could accelerate from rest to 100 km/h in 5.5 seconds.

All Q70 models had a seven-speed automatic transmission with adaptive gearshift behaviour and downshift rev matching.

Dimensions and body

Based on Nissan’s FM-L platform, the Infiniti Q70 sedan was 4945 mm long, 1845 mm wide, 1509 mm tall and had a 2900 mm wheelbase. Furthermore, the Q70 had double-wishbone front suspension and independent, multi-link rear suspension.

Safety equipment

Standard safety equipment for the Infiniti Q70 included dual front airbags, front side airbags, full-length curtain airbags, ABS, electronic brake force distribution, brake assist, electronic stability control, traction control, active front seat head restraints and front seatbelts with pretensioners and load limiters.

Both the Q70 S Premium and GT Premium editions were also fitted with:

• Blind Spot Warning (BSW) and Blind Spot Intervention (BSI): provided visual and audible warnings if another vehicle was detected in the blind-spot area (BSW). If the driver ignored the warning and attempted to steer into the other vehicle’s path, the brakes would be automatically applied on the opposing side of the vehicle to returns the vehicle to its original lane (BSI);
• Intelligent Cruise Control (ICC): enabled the driver to specify the desired speed and distance to the vehicle ahead. If the vehicle ahead slowed, ICC would automatically brake the vehicle to maintain the distance and resume the desired cruising speed as the vehicle ahead accelerated;
• Distance Control Assist (DCA): detected if the vehicle ahead was braking and provided feedback through the accelerator pedal to instruct the driver to remove their foot from the pedal;
• Forward Collision Warning (FCW) with Intelligent Brake Assist (IBA): laser sensors calculated the distance to the vehicle ahead and, if approaching too fast, would warn the driver. If the driver did not apply the brakes in time, IBA would automatically brake the vehicle;
• Lane Departure Warning (LDW) and Lane Departure Prevention (LDP): a camera mounted near the rear view mirror would detect lane markers and whether the vehicle was drifting into another lane without indicating. A warning tone would initially sound, followed by autonomous braking of the wheels on the opposing side of the vehicle if the vehicle continued to drift.

Q70 S Premium editions were also fitted with a Low Speed Following (LSF) system which operated between 5 km/h and 40 km/h by autonomously accelerating and braking the vehicle in traffic. Unique within the range, the M35h was fitted with Infiniti’s Vehicle Sound for Pedestrians (VSP) system which used an in-car sound synthesizer with a speaker built into the front bumper. VSP would emit a range of high-low sounds at different volume levels according to vehicle speed to warn pedestrians of its approach.

Brakes

The Infiniti Q70 GT editions were fitted with 320 mm diameter front and 308 mm rear ventilated disc brakes. The Q70 S Premium, however, was fitted with 355 mm ventilated front disc brakes with four-piston calipers and 350 mm rear ventilated discs with two-piston calipers.

Features: Q70 GT and GT Premium

Standard features for the Infiniti Q70 GT editions included 18-inch alloy wheels with 245/50 R18 W-rated tyres, a six speaker sound system with a CD/DVD player, MP3/WMA compatibility, 10GB hard-drive, auxiliary input (3.5 mm/USB/iPod) and Bluetooth audio streaming, satellite navigation with an eight-inch touch screen, dual-zone climate control air conditioning, cruise control, ten-way power adjustable front seats, heated and ventilated front seats, semi-aniline leather seat upholstery, bi-xenon headlights with washers and adaptive lighting, front and rear fog lights, front and rear parking sensors, a reversing camera, automatic headlights, rain-sensing wipers, a leather-wrapped and heated steering wheel, Bluetooth mobile phone connectivity, push-button start, remote central locking, power windows and heated mirrors, power folding mirrors with automatic tilt when reversing, a power adjustable steering wheel (tilt and reach), driver memory settings (steering wheel, mirrors, seat position and climate control), sunroof, an electrochromatic rear view mirror, two 12 volt power outlets, tyre pressure monitoring, an alarm and immobiliser. All M sedans were fitted with a space-saving spare alloy wheel.

Compared to Q70 GT, the Q70 GT Premium added a sixteen speaker Bose Surround Sound system and a powered rear sunshade.

Features: Q70 S Premium

The Infiniti Q70 S Premium was further equipped with 20-inch light alloy wheels with 245/40 W-rated tyres, sport-tuned suspension, contoured front sports seats and a sports steering wheel and gearshift knob. The S Premium was also fitted with:

• Four-wheel active steering (4WAS) which would actively turn all four wheels while cornering and adjust the steering angle and ratio according to the vehicle’s speed; and,
• Dynamic Cornering Enhancement (DCE) which would adjust the torque distribution between the rear wheels and apply the brakes to individual wheels to reduce understeer.

The Q70 S Premium editions could be identified by their unique front bumpers, dark chrome grilles and blackened headlight surrounds and reflectors. Inside, there were aluminium pedals, black lacquer trim and a graphite roof liner.

Brochure

• Brochure: Infiniti Y51 Q70 (August 2014)

Review: Infiniti Y51.II Q70 (2015-19)

Overview

Commencing production in November 2015, the Infiniti Y51 Series II (Y51.II) Q70 introduced a revised range as the 3.0d variants were discontinued. Visually, the Y51.II Q70 could be identified by its new LED headlights, double arch grille with waved mesh finish and chrome surround, front bumper with integrated fog lights, LED combination lights, flattened boot lid and chrome rear finisher. The Q70 S Premium was further distinguished by its unique front bumper for a wider stance and a high-gloss black finish for the lower part of the rear bumper.

According to Infiniti, the revised styling of the Y51.II Q70 improved aerodynamic efficiency, with drag coefficients of 0.26 Cd, 0.27 Cd and 0.28 Cd for the hybrid, GT and S Premium editions, respectively.

Safety equipment

Compared to their Y51.I predecessors, the Q70 GT Premium and S Premium were further equipped with ‘Backup Collision Intervention’ (BCI) which could autonomously apply the brakes if an object was detected behind the vehicle and there was a risk that the driver may reverse into it.

Features

Compared to the Infiniti Y51.I GT, the Y51.II GT edition was further equipped with a Bose sound system with ten speakers, LED headlights, LED daytime running lights and LED fog lights. While adaptive lighting was standard for the Y51.I Q70, however, it was reserved for the GT Premium and S Premium editions in the Y51.II Q70 range.

The Q70 GT Premium and S Premium both gained an ‘Around View Monitor’ (AVM) which used cameras located on all sides of the vehicle to generate a bird’s eye view of the vehicle which could be projected on the in-dash screen. The system also included corner parking sensors, moving object detection and parking guidance.

Specifications

• Specifications: Infiniti Y51 Q70 (February 2016)

Related links

• Infiniti Cars Australia: Infiniti Q70
• Wikipedia.org: Infiniti Y51 Q70