Future models - Subaru - Impreza - WRX STi
First drive: New Sube STi banishes boy-racers
Quicker, tricker and comfier new STi takes Subaru's Impreza WRX to a whole new level
9 Nov 2007
By JAMES STANFORD in TOKYO
SUBARU'S new Impreza WRX STi represents a significant change of direction for the Japanese car-maker that wants to be taken seriously as a prestige player.
The more upmarket model has more power, torque and outright performance than ever before but, as our first drive revealed, it's also more comfortable, quieter and far more subtle when it comes to styling - without sacrificing handling.
A higher pricetag will further distance the 'grown-up' new STi from 'boy racers' when it goes on sale here in February.
Subaru Australia has not announced pricing yet, but says the two different versions will be offered "between $60,000 and $70,000", which is a significant step up from the outgoing model's $56,990 sticker.
The new pricing pushes the new STi further up and away from the WRX upon which it is based, which now costs $39,990 and creates space for a model to sit between the two cars, which is something Subaru is now considering.
Subaru Australia says that customers of the previous STi felt the car was not different enough to the standard WRX, given the extra cost.
That has all changed with the new STi, which not only has unique mechanicals, but also a custom body.
Subaru spent a significant amount of money to give the STi a much meaner look, with pumped-out wheel-arches and a wider track announcing to the world that this car really is something special.
Only the bonnet, front doors, roof and rear hatch are carried over from the regular WRX.
The only other STi with a custom body was the two-door version of the original generation that arrived in Australia in 1998.
Until now, all STi models have been based on sedans. However, even though a sedan version of the WRX will arrive in Australia next August, there will be no STi sedan.
Why is the STi a hatch? The answer lies in the World Rally Championship, explains Subaru Australia managing director Nick Senior.
"The hatch is the optimum style of vehicle needed for success in WRC," said Mr Senior.
"We wanted a longer wheelbase with shorter overhangs at the front and rear." There is also the added benefit, not that WRC drivers would care, of increased interior space including good rear headroom.
Subaru's WRC ambition is also reflected in the beefier wheel-arches and wider track which give it a bigger footprint.
Mr Senior said Subaru designed what it wanted from a WRC car and the result was the STi, from which the company designed the WRX.
"The STi (in terms of body) is pretty much the WRC car, except that it may run a different spoiler," he said.
The STi runs a unique front bumper with large foglights and a specific rear bumper that features a large aerodynamic diffuser.
It also has a hatch-mounted spoiler that is more subtle that the previous STi's massive boot-lid spoiler.
Unlike previous STi models, the new model features a steel bonnet rather one made from lighter aluminium. Subaru said it reverted to steel because it was easier to produce the shape of bonnet needed for ever tightening pedestrian crash safety tests.
Despite the slightly heavier bonnet, the new STi's body is actually lighter than that of the previous model, but extra features mean the new car is 10kg heavier overall at 1505kg.
The new STi is the first production Subaru to officially produce more than 206kW, the self-imposed limit set by Japanese manufacturers.
It was known as a gentleman's agreement and described by the car-makers as a "mutual self-restraint agreement. Either way, it's now well and truly finished.
There are two different four-cylinder engines fitted to the STi, the 2.0-litre for Japan and a 2.5-litre for all export markets.
The 2.5-litre turbo boxer is essentially the same as the previous engine, but Subaru has made a series of revisions to boost power from 206kW to 221kW at 6000rpm, and peak torque from 392Nm to 407Nm at 4000rpm.
The improvements come from an improved valve timing system. Previously, the STi's inlet valve was variable, but not the exhaust valve. Now they are both variable, which has not only increased the peak performance, but made the engine more responsive by widening the powerband.
Other changes include a bigger intercooler, different turbo, a freer-flowing exhaust including less back-pressure and the re-positioning of the catalyst closer to the engine.
European tests have found the new STi dashes from 0-100km/h in 5.2 seconds, but Subaru Australia has not yet tested the car and could produce a different result.
Given the new STi has considerably more power and is only slightly heavier, it is expected to be faster than the previous model that managed the 0-100km/h run in 5.4 seconds.
While the new Mitsubishi Lancer Evo will be offered with both manual and dual-clutch automated transmissions, the new STi is only available with a six-speed manual gearbox.
Subaru says it is still considering whether it should develop a dual-clutch auto for the STi and has no firm plans to introduce one.
The STi benefits from the new Impreza suspension set-up which comprises an inverted MacPherson strut front-end with forged aluminium lower arms and a double-wishbone rear system.
It has been specially tuned, taking advantage of a front track that is 40mm wider and rear track that is 45mm wider.
The new STi has a firmer tune than the cooking-variety WRX, but it is much softer than the previous model.
STi project manager Hiroshi Mori said the suspension of the previous model was so firm that its wheels would lift and skip over bumps and therefore lose contact with the surface, reducing grip levels.
The new set-up allows the car to being driven quicker because the tyres are more in contact with the surface, says Subaru.
WRC ace and Subaru works driver Petter Solberg had significant input and pushed for a softer tune which he argued would not diminish traction levels or handling capabilities.
The new suspension could also draw some customers back to the STi who steered clear of the existing model due its bone-jarring ride.
Subaru made some minor revisions to the STi body, increasing the thickness of the steel used around the rear hatch for extra stiffness.
The new STi features a more advanced control systems than the previous models.
Firstly, the standard electronic stability control can be switched off completely. If you are feeling a little sporty, but still want some ESC assistance if you really get into trouble, simply hold the button down for longer. Doing so lowers the ESC threshold.
The STi also features the SI-drive feature which controls the engine control unit mapping. Flick the dial and throttle response is sharpened.
More interesting for enthusiasts is the Driver Controlled Centre Differential (DCCD), which has been upgraded.
There are now three different differential control maps, while the driver still has the ability to manually set the drive split between the axles between 50/50 front/rear and 41/59 front/rear.
The standard control setting is 'Auto', which alters the rate of drive between the front and rear for optimum traction.
Drivers can now also select 'Auto +' and 'Auto –' for even greater control.
Picking 'Auto +' locks the centre differential at 50/50 and is better for slippery conditions.
Locking it into 'Auto –' loosens off the centre differential and allows for more power to be fed to the rear coming out of corners when grip levels are good.
The STi runs a helical front limited-slip differential (LSD), a Torsen rear LSD and a mechanical centre differential that is paired to an electronic LSD.
Braking has not been ignored and the STi runs potent anchors developed by Brembo, including four-pot front callipers with ventilated discs.
The regular STi will come with five-spoke 18-inch alloy wheels, while the more expensive model will be fitted with 18-inch BBS lightweight 16-spoke wheels.
The only other difference relates to the seats. Subaru will fit the regular STi with sports seats lined with a mix of Alcantara and leather, while the higher-grade model is fitted by body-hugging leather and Alcantara-trimmed Recaros.
It is expected the higher-grade STi model will come at a price premium of around $5000.
Satellite-navigation will be offered on both STi models as a separate option.
The interior of the STi is similar to the WRX, but features a different instrument cluster with a rev indicator, DCCD setting information and a light that comes on when it is time to change gears.
Red lighting is used to back-light the dials and an STi logo on the unique centre console that glows at night. The STi also features a three-spoke leather-wrapped sports steering wheel.
Standard safety equipment includes twin front, side and curtain airbags which is a big improvement given that the last STi only had front airbags.
Drive impressions:THE STi has become civilised.
There are many clues, but just look the wheels as an example.
Subaru will offer the car with in several colours including traditional WRC blue, but there will be no gold wheels.
That's right, the iconic rims that evoke images of Subaru rallying heroics, thanks largely to Colin McRae, and which were unique to STi cars, are gone.
They may well reappear as a limited-edition, especially if fans revolt in the street, but in many ways Subaru wants to distance itself from the overt nature of previous models.
Its Australian division is ashamed of all the previous-generation STis that have fallen into the hands of young guys with baseball caps who fit a massive thundering exhaust pipe and piercing blow-off valve, and wants to move the performance brand upmarket.
Judging from an initial test drive at the tight Honjyo track north-west of Tokyo this week, Subaru has succeeded in making this car more of a sophisticated and comfortable machine.
Whether it stays true to everything that makes a WRX STi depends on your view.
If you want big wings, a larger-than-life scoop, a brutally stiff ride and a lot of noise inside the cabin, the new STi will let you down.
Those who want to drive the car daily and not be identified instantly as a boy-racer will love it.
From the first corner, you notice how much softer this car is over its predecessor.
It doesn't wallow in corners, but there is initially some bodyroll and the nose does dive a little under heavy braking.
That said, the new softer setting doesn't appear to affect the pace at which you can push through most turns.
The bodyroll is not extreme and the supreme traction set-up of the STi means there's no problem getting the power down coming out of the turn.
To put it simply, it is still an incredible amount of fun to push hard around a racetrack.
Subaru had set up a bumpy gravel road near the track and requested we drive slowly along it in the STi and then a Volkswagen R32 to get an idea of the ride comfort of both cars.
The VW came off second-best with a far harsher ride that picked up most of the bumps, while the STi did a far better job of absorbing them.
It was promising, but the real test will come on real-world local roads. The early signs suggest the kidney-bruising, teeth-rattling ride quality of the previous STi are gone.
It is likely the plush new ride will bring some customers back to the brand who simply couldn't handle the busyness of the previous model or had partners who refused to put up with it.
Does the new soft suspension spoil the STi? We don't think so.
Many race cars are set-up super-firm, but there are others that use a softer tune to ensure maximum traction by keeping as much of the tyre on the ground as possible at all times.
It's not like the new STi feels like an American car with marshmallow ride, but in a quick change of direction it feels like it takes a little longer to switch position.
The STi's steering feedback is still good and well-weighted.
And Subaru has not messed with the fundamentals of the powertrain. This is a delightful engine that is better than ever before.
It is more responsive through the entire rev-range, especially down low, and has enough torque to happily pull out of a hairpin bend in third gear.
The engine is very smooth and delivers its power in a very linear way, a far cry from the early STis that delivered very little down low before unleashing with massive force mid-way through the rev-range.
The sheer acceleration is enough of a thrill, but the STi also delivers a lovely meaty exhaust note that announces to the world this is a potent boxer engine.
According to some who have driven the Japanese STi, this aural aspect is missing from the new 2.0-litre engine.
Having a shift light is a nice touch, but in reality, few drivers will be caught out by the rev-limiter.
The 2.5-litre unit doesn't spin up as quickly as other smaller units and has so much low to mid-range torque that there's isn't much point in wringing its neck at the very top of the rev range.
Subaru could lose a few sales by not offering a DSG automatic, especially as many older folk who might now consider the softer STi prefer autos.
The company says rally heritage is built on manual gearboxes, but rally cars don't need to crawl along in city gridlock on the way into the office.
While some customers would like the choice of an auto, the manual is a very good unit with a clear and crisp feel.
The traction levels of the STi are, as you would expect, stunning.
We like the amount of complexity Subaru has built into the car, which gives the owner the ability to set-up the car just the way they want it.
To be honest, the different centre differential control maps didn't seem to make all that much difference on the flat and dry track.
It felt like it turned in very slightly better in the 'Auto – ' mode, but the difference was minimal.
On gravel, slippery or bumpy tarmac, you could be far more likely to pick up on the nuances, but it would have taken a lot more time on a familiar track to really notice the difference.
We suspect that, as in the past, most customers will simply leave the centre differential controller in the 'Auto' position and let the car decide what's best.
The SI Drive control is nice to have, but it is an awfully big dial considering all it controls is the engine mapping.
Given that pressing it simply sharpens the throttle control, it could have simply been designed as a small Power button that is less in-your-face.
The ability to turn off the traction control in stages is a good feature.
It is strange that pressing the ESC button once turns all stability assistance off, while you have to hold the button down for longer to have the ESC threshold reduced, but still on in the background.
Surely, a better set-up would be to access the lower threshold ESC mode by pressing the button and then go to the no-assistance mode by holding the button down, as in other cars. We tip that this could cause some confusion.
The interior has been improved over the last model and the mix of leather and Alcantara for the seats and door sections gives the STi a classy look. Gone are the bright blue trim sections from the previous cars.
The standard seats look good and offer some support, but perhaps not as much as you need for such a performance car.
With a pricetag above $60,000, you shouldn't have to pay extra for more supportive seats and it is the same with the wheels.
The BBS rims look fantastic and make the standard five-spoke alloys look ordinary, which is a bit much given the pricetag of the standard STi.
Subaru has done some work raising in the level of interior feel for this car and the unique instruments lift the look, as does the centre console with the glowing STi logo and the varying controls.
Unless you pay extra for the sat-nav, the dashboard is still missing a quality information display screen.
It has to make-do with a thin mono-colour digital display above the sound system that could have come from much cheaper cars and there's no distance-to-empty reading.
This doesn't cut it for a car at this price as a lot of customers want to access information on a high-resolution colour screen. If the Ford Mondeo XR5 can do it for considerably less money, then why can't the STi? Subaru says that the level of tyre, engine and road noise has been dramatically reduced.
We will have to wait until local test drives to see if this is the case as the smooth bitumen of a racetrack didn't simulate real road conditions.
The engine bay certainly did feel well insulated on the track, with little noise apart from the lumpy exhaust note making it into the cabin.
The new STi is a very practical car. Its rear leg and headroom are impressive and it has a nice big boot.
With its new softer suspension, it could be used to cart a younger family around without complaint.
The styling of the new Impreza and especially the WRX is controversial. It looks bland and from some angles, especially the side, it appears to be a clone of other Japanese models (ie: Mazda3).
The STi has no such problems. If you can't pick the big pumped-out wheel-arches and wider track from a distance, you need your eyes checked. Another prominent clue is provided by the four big pipes nestled in the rear bumper and the plastic rear-diffuser.
There are nice small touches like the air-vents in the front guards that show Subaru has put a lot of work into these unique panels.
In the metal, as well as in these pictures, the STi looks great.
If the world saw this car first and then the watered-down WRX, the new design may have not have met with such harsh criticism.
It will be expensive, but the STi is clearly a far better car than the model it replaces.
It's faster, has tremendous traction, looks the business, still sounds great and has comfortable ride without compromising its handling.
Now all that is left is the tantalising question: how will it stack-up against its traditional rival, the Lancer Evo X?
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