It appears to be a stop-gap measure as Subaru has simply raided its parts bin rather than design an all-new gearbox; the five-speed auto is the same transmission used in its large softroader, the Tribeca.
Indeed, the gearbox appears to be untouched, as Subaru has had to cap the torque output of the STI’s otherwise impressive 2.5-litre turbo four-cylinder engine.
Power, curiously, is the same for both the manual and automatic versions (at 292bhp it is also unchanged from last year’s model). However, while the six-speed manual WRX STI has 300lb ft of torque, the auto must make do with 258lb ft.
I’d like to say that you can barely notice the difference, but the reality is: you can.
Against the stopwatch, the auto is almost a full one second slower in the 0 to 62mph dash than the manual, completing the task in a rather leisurely six seconds neat.
And it’s not because the auto version is 10kg heavier than the manual. It just doesn’t have enough grunt.
The automatic shifts are quite smooth, and as with its peers the WRX STI auto comes with a nice pair of levers behind the steering wheel so you can select gears manually. But manual gearchanges are slow and blurry, and the system won’t allow you down-change if doing so means the engine is likely to be within a few thousand rpm of its maximum revs.
It’s all a bit ham-fisted really. Thankfully, the manual still offers blistering performance and the wider body means the sedan gets the wider track for better cornering grip.
Subaru has also used the opportunity to update the suspension tuning; the new model is more compliant over ruts in the road than its predecessor. And while there is still plenty of road roar that is typical of Japanese performance cars, it is muted slightly by some extra sound deadening material.
The high performance Brembo brakes are as good as ever, able to cope with whatever repeated punishment is dished out to them, but they still have a slightly too-firm, wooden feeling for my liking.
Should I buy one?
In case you hadn’t guessed by now, the manual is still the pick of the two transmissions and it comfortably holds its own against its manual-shifting peers. However, auto for auto, the WRX STI is comprehensively outgunned. Despite this, Subaru Australia believes the auto will account for 70 per cent of WRX STI sales locally. Hopefully, customers in Great Britain will have more sense and opt for the manual.
Subaru Impreza WRX STI automatic
Price £28,000 (est); Top speed: 155mph; 0–62mph: 6.0sec; Economy: 22.1mpg; C02: 249g/km; Kerb weight: 1495kg; Engine: 2457cc turbocharged horizontally-opposed ‘boxer’ four-cylinder petrol; Power: 292bhp at 6200rpm; Torque 258lb ft at 4000rpml; Gearbox: five-speed torque converter automatic
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