2014 SUBARU WRX STI
2014 SUBARU WRX STI
- All new exterior design for Subaru’s flagship sports saloon
- Extensive re-work to chassis for improved handling and ride
- New hydraulic steering system
- Symmetrical All-Wheel Drive and 2.5-litre turbo Boxer engine
- Larger, higher quality cabin and greater practicality
- Extensive standard equipment includes standard 18-inch alloys
- From £28,995 (OTR)
The new Subaru WRX STI – the Japanese brand’s iconic four-door sports saloon – returns to the UK this summer with a distinctive new look, an all new interior, the promise of even better handling and feelsome steering, and, of course, the car’s renowned turbocharged performance.
The muscular proportions of the WRX STI convey a sense of power and stability. For the new-generation model, key design themes found on previous-generation models – notably the bonnet scoop and large rear spoiler – are still there, but have been evolved to give a more sophisticated yet purposeful look.
Subaru’s 2.5-litre turbocharged Boxer engine – generating the evocative Subaru ‘burble’ exhaust note – is complemented by the brand’s Symmetrical All-Wheel Drive technology, giving the car unprecedented levels of performance and traction. Agility and driving enjoyment are further enhanced by the car’s low centre of gravity, the new hydraulic steering and re-worked short-throw gear shift.
Subaru is confident that the WRX STI will be one of the most satisfying performance cars on the road when it goes on sale this May.
The engineering brief for the new WRX STI was to develop a car that provided absolute power and driver control. With 300ps and 407Nm of torque on offer from the engine, and a drivetrain that allows the car to apply the maximum power and torque to the road at all times, the WRX STI is one of the fastest – and safest – performance cars in ‘real world’ conditions.
The WRX STI’s new hydraulic power steering has been designed to not only give more driver ‘feel’ but also even quicker turn-in. Combined with a revised, short-throw six-speed gearbox the WRX STI offers increased responsiveness to driver inputs and progressive, linear handling to make it an engaging and rewarding car to drive.
The new WRX STI is also more spacious and more comfortable than its predecessor, with a high level of standard equipment. Interior appointments and ambience are much improved over the old model with soft-touch materials used in key areas on the doors and dashboard. The new model is adorned with a race-derived D-shaped steering wheel, while Alcantara and leather sports seats hug the driver and front passenger.
A revised suspension system improves ride comfort without sacrificing the handling characteristics that have made the WRX STI so successful on the road and track. A stiffer body shell and advanced powertrain management system endow the car with the highest standards of active and passive safety performance.
Isle of Man TT – four-wheeled lap record holder
In June 2014, the all-new WRX STI beat its own four-wheeled lap record around the famous Isle of Man TT circuit, with British Rally champion Mark Higgins at the wheel. The car completed a lap of the 37.75-mile course in just 19 minutes 15.9 seconds, travelling at an average speed of 117.51 mph. The new time eclipsed the record laid down by the previous-generation WRX STI in 2011, which completed the lap in 19 minutes, 56.7 seconds.
The WRX STI used for the record breaking run was a standard Subaru production car (in USA specification), equipped with the same 300ps 2.5-litre horizontally-opposed turbocharged Boxer engine as the production model and featuring unmodified brake callipers and road-legal tyres. The springs and damper were adjusted slightly to minimise any potential damage when the car encountered the many bumps and jumps at high speed along the course, and the car was fitted with the requisite safety equipment for high-speed track driving.
The new Subaru WRX STI will be available to UK buyers in a single trim level, with a six-speed manual transmission and All-Wheel Drive as standard. The car will be available from £28,995 (on-the-road) – £4,000 less than its predecessor – representing superb value for money for drivers seeking a well-equipped high performance sports saloon.
Price OTR (£)
WRX STI 2.5i Type UK
- Iconic model gets distinctive new look
- A-pillars moved forwards for more coupé-like silhouette
- Body shell is 140 per cent stiffer with no weight gain
- Unique boost gauge for new model
The new Subaru WRX STI builds on the model’s role as the brand’s flagship performance saloon. The all-new body further develops the model’s iconic appearance, with more distinctive styling. A low, wide body emphasises the car’s stability, presence and sporting intent.
The body shell of the new WRX STI incorporates a higher percentage of ultra high-tensile steel. This has resulted in a body that is 140 per cent stiffer than the previous model, yet with no increase in weight.
Reinforcements at strategic points around the body minimise chassis flex, improve steering response and enable greater suspension refinement to provide a more supple, well-controlled ride.
The front of the WRX STI displays Subaru’s trademark hexagonal grille, now in gloss black, while the newly-designed hawk-eye LED headlamps and lower placement of the front fog lamps highlight the car’s wide and low stance.
The bonnet scoop, a feature of the car’s predecessors, is now positioned closer to the front of the nose and is embedded further into the bonnet, reducing its visual height while improving aerodynamic efficiency and air intake control. The revised bonnet structure also improves the car’s pedestrian-impact crash safety performance.
The WRX STI’s sculpted profile sees the base of the A-pillar moved forwards by 200mm, while the C-pillar transitions more smoothly into the prominent belt line. Combined with a lower roofline and a new shark-fin audio antenna, these subtle changes make the car’s appearance more coupé-like.
Squared-off wheel arches, featuring vents behind the front wheels, lend the car an air of solidity and stability and manage air-flow around the car. Wider, shorter door mirrors look sportier than those found on earlier models yet improve rearwards visibility.
At the rear of the car, the prominent bumper incorporates the four exhaust pipes and an integrated black diffuser, emphasising the car’s low centre of gravity and sportiness, while the familiar WRX STI rear spoiler features prominently. This is 8mm higher than that of the previous-generation, improving rear visibility from the driver’s seat. The drag co-efficient of the spoiler remains the same and weight is reduced by 0.3kg.
Compact LED tail lights and braking lights give the car a unique night-time light signature.
The WRX is available to UK buyers in a range of four body colours – Crystal White Pearl, Dark Grey Metallic, Crystal Black Silica and Subaru’s iconic World Rally Blue.
The all new cabin of the WRX STI leaves drivers in no doubt as to the car’s performance intentions.
The small-diameter D-shaped steering wheel sits in front of an instrument binnacle housing a dual-dial layout with 3.5-inch full-colour LCD and aluminium rings for a sporty look. The red lighting is suitably evocative and is made more noticeable by the contrast with the white needles.
Sports front seats, complete with embossed ‘STI’ logo on the head restraint, are finished in Alcantara with leather side bolsters and have been shaped to be both supportive but also supremely comfortable. There are further red highlights on the black seat upholstery, while stainless steel sill plates, additional red lighting elements and carbon fibre-look trim on the centre console enhance the performance car ambience. At the same time, all the controls have been designed to be simple and intuitive to use.
Higher grade materials – including soft-touch dashboard and window sills and Alcantara inserts on the doors – further raise the appearance and quality of the cabin.
In moving the A-pillar further forward, the WRX STI has greater natural lighting than previous models while improving the driver’s forward visibility.
Unique Multi-Function Display
A new Multi-Function Display (MFD) – with functionality unique to the WRX STI – is positioned at top-centre of the dashboard to allow drivers to monitor the car’s performance functions and capabilities.
The 4.3-inch LCD colour screen displays a number of functions for everyday driving, with separate screens for audio, calendar and clock, fuel economy, active safety and status of the All-Wheel Drive system, outside temperature and vehicle health check.
Unique within the Subaru range, the MFD in the WRX STI offers an additional boost gauge screen option, providing analogue and digital representations of the accelerator opening, current boost pressure and boost pressure peak value. This can heighten driving enjoyment and is useful for those owners who will take their car on track.
3. Chassis and running gear
- Upgraded suspension enables greater agility and improves ride comfort
- Hydraulic steering system, quicker rack aids turn-in
- 17-inch ventilated disc brakes offer greater stopping power
The suspension and running gear for the new WRX STI are an evolution of existing Subaru technology, with revisions designed to improve driver satisfaction, steering feel and braking performance.
Revised suspension and steering systems
The front suspension is fully independent and uses compact MacPherson struts with enhancements to improve damping control, steering response, agility and ride comfort.
There are stiffer cross members and control arm front and rear bushings for a more linear steering response, improved handling performance and reduced road noise. A thicker front anti-roll bar reduces roll and improves stability, while the front suspension’s transverse link rear bushings are mounted 10mm lower to improve ground contact for the front inner wheel under cornering, further improving traction and stability.
The WRX STI’s fully-independent rear suspension now features a thicker anti-roll bar, stiffer sub frame bushings and new rear sub frame supports to improve stability and steering response. Lowering the rear sub frame front mounts for the suspension’s lateral links has added 3mm of initial toe-in, generating quicker lateral force for improved steering response. The shock absorber mounts have been moved outwards by 10mm to provide improved damping.
The WRX STI continues to employ a hydraulic power steering system to provide a high level of steering feel to drivers. For right-hand drive models sold in the UK, the new steering system offers improved turn-in, with 15 per cent quicker ratios than the previous model (altered from 14.8 to 12.7). The steering torsion bar in the new model is 125 per cent stiffer than the previous version’s, further improving steering response and feel.
Modifications to the suspension ensure the new WRX STI is more agile than ever before, generating lateral G-force just 0.1 seconds after turning. This is half as much G-force lag as a Volkswagen Golf GTI (0.2 seconds) and on-par with the Porsche 911 Carrera S against which the WRX STI was benchmarked dynamically throughout its development.
Upgraded brakes and lighter wheels
The WRX STI employs the same 17-inch Brembo disc brakes as the previous model (four-pot callipers on the front and two-pot callipers on the rear). The brake booster has been tuned to provide quicker brake response and the master cylinder has been enlarged by seven per cent to increase braking power.
The more responsive brakes are housed in new 18-inch alloy wheels which are 15 per cent stiffer than those found on the earlier model and each 1kg lighter. The new wheels achieve a greater balance between reduced weight, component strength and reliability, and aerodynamics. The WRX STI is equipped with custom-made 245/40 R18 high-performance Dunlop SP Sport Maxx tyres.
- Multi-mode driver-controlled centre differential tailors car for road or track driving
- Symmetrical AWD and torque vectoring improve traction in all conditions
Symmetrical All-Wheel Drive
The WRX STI retains Subaru’s legendary Symmetrical All-Wheel Drive (AWD) system with a centre differential, which allows drivers to safely exploit the car’s high levels of traction, stability and agility.
Multi-mode driver-controlled centre differential
Combined with its manual transmission, the WRX STI features a centre differential incorporating a viscous limited-slip differential (LSD). The basic torque distribution is set at 50 / 50 per cent front / rear and whenever a front or rear wheel slips the viscous coupling adjusts the torque distribution to optimise traction. The system employs a torque vectoring system to further improve traction and grip at front and rear.
In the previous-generation model, the centre differential operated in one of two modes, manual or auto mode. The new model gives the driver a manual mode plus three pre-set ‘Auto’ modes to choose from, according to road and track conditions and driver preference.
‘Auto’ Mode, the default setting, provides the best balance between agility and traction for everyday driving conditions. ‘Auto+’ Mode limits torque in order to improve traction on slippery road surfaces and when stability is most important. ‘Auto-’ Mode increases steering responsiveness and allows more torque to be distributed to the rear of the car, allowing a greater degree of agility and throttle adjustability.
Three-mode SI-Drive system
The WRX STI benefits from a custom driving mode system, Subaru Intelligent Drive (SI-Drive), which allows drivers to select one of three modes to alter engine and throttle response.
Intelligent (I) Mode carefully monitors driving conditions to deliver optimum fuel efficiency and smooth power delivery. Sport (S) Mode is the most versatile for all conditions, offering linear power delivery across a wide range of engine speeds with slightly more urgent throttle response than I Mode. Sport Sharp (S#) Mode allows drivers to extract the maximum response from the 2.5 litre Boxer engine, with more direct throttle response and closer, more precise rev control across all engine speeds.
5. Engine and transmission
- 2.5-litre turbocharged Boxer engine produces 300ps and 407Nm
- Revised for greater mechanical efficiency and accessible performance
- Reduced turbo lag and throttle response for greater acceleration
- Euro 6-compliant
The new Subaru WRX STI is fitted with an evolution of the existing 2.5-litre horizontally-opposed Boxer engine found in the previous model. The revised engine retains the proven benefits of the horizontally-opposed layout while achieving greater mechanical efficiency and a more immediate accelerative response.
Generating 300ps at 6,000rpm and 407Nm torque at 4,000rpm, the engine powers the WRX STI from 0-62mph in 5.2 seconds and on to a 159mph top speed. The WRX STI returns fuel economy of 27.2mpg on a combined cycle and CO2 emissions of 242g/km.
Improved accelerative response
Throughout the development programme for the WRX STI, the aim of Subaru’s vehicle engineers was to create an engine that can provide decisive acceleration at any engine speed and in any gear.
Changes to the engine include a larger intercooler to improve engine cooling efficiency and modifications to the ECU to enable more precise tuning of boost pressure control to reduce turbo lag and improve acceleration response.
As a result of these improvements, when accelerating at 40mph in third gear in S Mode (using the SI-Drive driving mode controller), the WRX STI can accelerate at 2.0m/s2 after just 0.5 seconds, compared to 0.9 seconds on the previous generation. In the same gear, forward acceleration also now peaks at 3.2m/s2, compared with 2.5m/s2 in the previous model.
The 2.5-litre Boxer engine is fitted with Subaru’s dual intake and exhaust Active Valve Control System (AVCS), which enhances mechanical efficiency and improves acceleration response by varying the timing of the intake valves to provide optimum air flow in and out of the engine. AVCS optimises torque between 2,000 and 4,000rpm, the engine speeds typically used by owners on a day-to-day basis, and improves acceleration response at higher engine speeds.
Fewer harmful emissions
To ensure the engine complies with Euro 6 emissions standards, a new secondary air system introduces recycled warm air to the exhaust port of the cylinder head. This reduces hydrocarbon emissions when the engine is started by reigniting any unburned fuel and helping the catalytic converter to start working earlier.
Six-speed manual gearbox
The standard transmission for the WRX STI is a six-speed manual. This has been refined in the new model for easier, more satisfying gear changes, a shorter throw and improved NVH performance.
In addition to producing a sportier gear change, revised scissor gear springs reduce the level of noise from the gearbox and lessen vibrations through the unit. The shift detent mechanism was also improved, with new profiles for each detent on the shift rods enabling a smoother and more tactile gear change.
Carefully-selected gear ratios, optimised in line with the engine’s improved response time, ensure that the WRX STI is able to offer drivers decisive acceleration in all driving conditions.
6. Practicality and packaging
- WRX STI gets longer wheelbase and lower roofline
- Wider, more practical cabin and larger 460 litre boot
Central to the appeal of the Subaru WRX STI is its excellent balance between high performance and practicality. These traits ensure the four-door sports saloon is well-matched to everyday life.
The WRX STI’s lengthened wheelbase (up 25mm to 2,650mm) and improved packaging are key elements in delivering greater practicality than ever before, though the vehicle has grown only by 15mm in total length, to 4,595mm. Width stays the same (1,795mm), but the side sills have been lowered by 20mm and pushed outward by 15mm, freeing up more space in the cabin, which is now 15mm wider.
The roof height of the WRX STI is reduced by 5mm to 1,465mm, increasing aerodynamic efficiency and enabling a cleaner side profile.
By moving the base of the A-pillars forward by 200mm compared with the previous model, the WRX STI benefits from a greater sense of spaciousness for front seat occupants. Combined with an instrument panel set lower than in earlier models, the repositioned A-pillars improve the driver’s field of view and make it easier to place the car accurately on the road.
Extending the wheelbase has created greater space for rear-seat passengers, with more leg, shoulder and elbow room than in earlier versions of the car. A raised hip point – up 20mm – improves the feeling of spaciousness in the rear, improves visibility for passengers and makes it easier to get in and out of the vehicle.
The driver’s seat has been redesigned to maximise comfort and visibility, and to increase support during more spirited driving. The new seats feature a wire running between the shoulder pads, reshaped side bolsters and shoulder pads and higher, firmer thigh supports to ensure greater support under cornering. The seat springs in the new WRX STI have been tuned to more evenly distribute body pressure throughout the seat, while new lumbar supports for front occupants improve comfort during longer drives and make it easier to find the ideal driving position.
Saloon car practicality
The new WRX STI has been designed to be as useable and convenient as possible for owners. It provides a generous level of storage space throughout the cabin and around the driver’s seat. Four large door pockets can hold bottles easily, while greater provision has been made to accommodate smaller items, such as wallets, smartphones and portable music players, with a larger central storage tray, covered centre console box and larger armrest storage.
Changes to the dimensions of the new WRX STI ensure that cargo capacity is increased by 40 litres to 460 litres, while a 60 / 40 split-fold rear seat folds forward easily to create an almost-flat cargo bay.
Making the front door openings larger by 125mm, as well as lowering the side sills, has resulted in superior accessibility.
- Revised multi-mode Vehicle Dynamics Control for improved hazard avoidance
- Switchable Traction Control System with new ‘Traction’ mode
- Wider field of vision from the driver’ seat
- Greater use of ultra high-tensile steel for 140 per cent stiffer body
The all-steel unitary structure of the Subaru WRX STI is engineered to deliver the highest level of crash safety performance while also providing a comfortable ride and a high level of refinement.
Active safety features
Subaru’s version of ESP, the Vehicle Dynamics Control (VDC) system, complements the superior driving stability of Symmetrical All-Wheel Drive and is standard on the new WRX STI. For this new model, the multi-mode VDC system was revised to provide world-class hazard avoidance capability. The operational status of the VDC is displayed on the Multi-Function Display.
VDC has been refined to cut yaw more efficiently during extreme cornering manoeuvres and now also operates the emergency brake assist system. This system assesses the need for braking assistance according to the braking force applied by the driver and the speed at which the brake pedal is depressed. The result is almost identical braking performance on both wet and dry surfaces.
The WRX STI allows owners to switch off both the multi-mode VDC and Traction Control System (TCS), making the car more effective on track. By selecting ‘Traction’ mode, the torque vectoring system remains engaged, but drivers are able to deploy maximum engine power without electronic intrusion by TCS.
Improved field of vision
A range of measures has been adopted to boost active safety to help accident avoidance. Forward visibility is improved by moving the base of the A-pillars forward by 200mm and lowering slightly the dashboard top. Thanks to the use of ultra high-tensile steel, the A-pillars are thinner than those on the previous-generation car, further improving visibility. Rearward visibility is also improved, by wider door mirrors which offer a wider field of view, and the larger rear spoiler, which is now 8mm higher and further out of the driver’s rear line of sight.
Night-time visibility benefits from new headlamps with an expanded field of illumination, while higher-mounted stop lights are more visible to following drivers.
Maximising protection through passive safety
For maximum impact resistance, the WRX STI body shell is equipped with a series of circular links which strongly protect the cabin occupants. Ring-shaped reinforcement frames join the A-, B- and C- pillars with cross members at roof and floor levels.
The new WRX STI employs a higher proportion of ultra high-tensile steel for key sections of the bodyshell, achieving a 140 per cent increase in torsional rigidity without adding to overall weight. Ultra high-tensile steel has been used to reinforce the front crash structure, side sill and A-pillar, which are the main structural parts of the cabin for occupant protection; the B-pillar, for greater side impact protection; and along the roof rail, to improve occupant protection in the event of impact on the roof.
The side of the vehicle now features high-strength cross members, helping to minimise body deformation in the event of a side collision, while the shape of the rear bumper structure has been optimised to dissipate impact energy along the now-strengthened side sills.
Pedestrian protection is enhanced thanks to the fitment of a higher proportion of energy-absorbing materials inside the engine bay and repositioning the bonnet scoop closer to the nose of the vehicle.
The WRX STI has stiff seat frames with tall backrests and separate energy-absorbent headrests to alleviate whiplash forces and minimise injury. In the rear seats, the cushion shape is designed to hold adult occupants firmly in place, with two ISOFIX anchors fitted for child safety seats.
Front, side and curtain airbags are fitted as standard, as well as a new knee airbag which cushions the driver’s legs in the event of a collision.
Other features enhancing occupant protection include a retractor mechanism for the brake pedal; a collapsible steering column; and a separation mechanism between the bodyshell and steering column to minimise the forces generated by the steering wheel pressing against the driver’s torso in a serious collision.
- Single trim level for the UK with generous standard equipment
- Optional full leather seats and satellite navigation
The new Subaru WRX STI’s standard equipment levels have been tailored to provide a comfortable and convenient cabin for driver and passengers. The WRX STI is available in a single trim level in the UK and is fitted with the following equipment as standard:
Front fog lamps
18-inch aluminium alloy wheels
Leather and Alcantara sports seats
One-touch lane change indicators
Safety and security
Front SRS airbags
Height-adjustable front seatbelt anchors
Six-speaker audio system
Three-mode SI-Drive system
Multi-mode centre differential
Pioneer satellite navigation
9. Technical Specification
Body and chassis
Four-door, five-seater saloon, with all-steel unitary construction bodyshell. Horizontally-opposed turbo Boxer petrol engine driving the front and rear wheels (AWD) via a six-speed manual transmission.
2.5-litre / 300ps petrol
Final drive 1 3.900
Symmetrical AWD with driver-controlled centre differential coupled to viscous LSD
Suspension and damping
Front Fully independent by subframe-mounted inverted MacPherson struts, with coil springs and gas-filled shock absorbers. Anti-roll stabiliser bar.
Rear Fully independent by subframe-mounted double wishbones, coil springs and gas-filled shock absorbers. Anti-roll stabiliser bar.
Type Hydraulic power-assisted rack-and-pinion
Min. turning circle 5.5 metres
Front 432mm ventilated discs
Rear 432mm ventilated discs
ABS 4-channel anti-lock system with EBD
BAS Boosts braking power to maximum during emergency stops
EBS Emergency Brake Assist
Wheels and tyres
Standard Alloy 18-inch x 8.5J 245/40 R18 Dunlop SP Sport Maxx tyres
Spare (standard) Tyre repair kit
Overall length 4,595 Overall width* 1,795
Overall height 1,475 Wheelbase 2,650
Front track 1,530 Rear track 1,540
Ground clearance 135 Turning radius 5.5 metres
*excluding door mirrors
Fuel tank 60 litres
Luggage (VDA) 460 litres behind rear seats (with tyre repair kit)
Kerb weight 1,534
Top speed / mph 159
0-to-62 mph / sec 5.2
Fuel efficiency (mpg)
Combined cycle 27.2
Urban cycle 20.2
Extra-urban cycle 33.6
CO2 g/km 242