2011 Subaru Impreza WRX STI Full Test and Video

Remember the raw, visceral, ball-breaking Subaru Impreza WRX STI? The STI that was an honest challenge for Mitsubishi's Lancer Evolution?

The STI that was both fast and engaging to drive? The STI that took textbook track drivers — all straight braking and late turn-in — and dirtied them up with ditch hooks, Scandinavian flicks and handbrake turns? Remember that car? Well, then you probably won't like this.

It's been emasculated.

And by emasculated we mean made slower. You see, with the 2011 Subaru WRX STI, Subaru promised a car that would distinctly separate itself from the base WRX. And now the gap has officially closed.

Uh Oh
When we last tested Subaru's WRX STI back in 2009, it hit 60 mph in 5.2 seconds and snorted through the quarter-mile in 13.5 seconds at 101.8 mph. In this test, conducted in ideal conditions and with the same driver behind the wheel, the 2011 STI hit 60 in 5.5 seconds and whimpered through the quarter-mile in 13.8 seconds at 97.4 mph.

Confounding the problem further, the 2011 Subaru WRX STI uses the same engine rated at the same power as the earlier car, its gear ratios and final-drive ratio are the same and it isn't significantly heavier. What's more, this performance is actually slower in the quarter-mile than the 2011 WRX we tested in September.

What's the Same
There are no real powertrain changes to discuss. Under the hood is the same 2.5-liter turbocharged flat four-cylinder engine that's powered the car since its inception. Yes, there have been modest changes to its power, torque and redline along the way, but there's nothing new to say about the powertrain for 2011 (at least that Subaru will admit).

It's rated at 305 horsepower and 290 pound-feet of torque and it's backed by the same six-speed manual transmission, which, in case you forgot, feeds power to all four wheels.

Subaru's Driver Controlled Center Differential, which utilizes both a mechanical (planetary gear-type) differential and an electronically controlled clutch to distribute torque, is still present. So are helical front and Torsen rear limited-slip differentials.

Every STI is also fitted with the utterly infuriating SI-Drive, Subaru's means of tweaking throttle response to suit its driver's needs. The system, however, provides barely adequate response even in its most eager setting (Sport Sharp), which must be engaged every time the ignition key is cycled.

What's Different
We once had a wise college professor who shared this idea with us: "A difference, to be a difference, has to make a difference." He was right.

Subaru of America, for its part, offers no explanation for these results.

Accordingly, we're not sure Subaru's changes to the 2011 Subaru WRX STI make a difference. After our first drive of the car in Colorado last summer we wrote that the suspension changes are "subtle but effective." Truth is, however, that the changes only truly register in certain situations and they don't show a significant improvement in our instrumented testing.

Still, underneath, they are substantial. Replacing the previously rubberized rear mount on both front lower control arms is a heim joint (pillow-ball mount if you're Japanese), which reduces deflection at this pivot. This, claims Subaru, increases steering control at high load. Stiffer bushings supporting the rear subframe are also new. Ride height is lowered by 10mm, spring rates are up 15.6 percent in the front and 53 percent in the rear and antiroll bars on both ends are thicker.

It's a comprehensive redo that should register a more significant change. The same Dunlop SP Sport 600 tires sized 245/4018 are fitted to lighter (4.4 pounds per corner) BBS forged wheels.

The Experience
As with most all-wheel drivers, 1st gear is gone too fast to make any useful observation. In 2nd gear, however, acceleration feels suspiciously off pace and by the time 3rd arrives there's a distinct sense that all the horses haven't shown up to the party.

Handling is a mixed bag. We can appreciate the impressive ride/handling balance Subaru has achieved, as the increase in spring rates hasn't translated into a proportional increase in ride frequency. And there are undeniably instances where fewer steering corrections are needed to hold a line, which is likely a product of the heim-jointed lower control arm. But, honestly, the differences as a whole are small enough that only those intimately familiar with the current STI will notice.

Still, we found the car capable — even at its lower ride height — of tackling rough roads (including gravel) without so much as a wimper. Blast sideways through a washboard-riddled turn and the STI's chassis doesn't even breathe hard. Our test car also endured repeated powertrain-abusing launches as we attempted to match previous test numbers.

The Numbers
The history of WRX STI tests performed in the last three years at Inside Line is a narrative of diminished performance. Our first full test of the current-generation STI proved the car capable of outpacing the car it replaced.

But then things began to change. Our long-term STI, which lived with us for more than a year, accelerated quicker at the end of its loan than it had at the beginning (the best numbers from its two tests are below). That car was 0.3 second quicker to 60 mph and 0.3 second quicker in the quarter-mile than this 2011 model.

Perhaps most telling is the fact that over the course of these three STI tests we witnessed trap speed drop by exactly 5 mph in cars that differed in weight by only 57 pounds. The only legitimate explanation for this reduced performance is a loss of power.

Performance in our standardized handling tests didn't improve despite the numerous suspension changes. Lateral acceleration actually decreased from previous STI tests (0.90g vs. 0.89g) and slalom speed fell somewhere in the middle of the other STIs at 70.3 mph.

At 112 feet, the 2011 Subaru WRX STI also required longer to stop than any other (current-generation) STI we've tested.

The Official Word
Subaru of America (SOA), for its part, offers no explanation for these results. In a statement issued after receiving our test results it says, "the numbers are within a few tenths of previous tests; we will investigate this matter."

And when asked about the motivation to buy an STI in light of the WRX's strikingly similar performance, SOA offered the following:

"The motivation to purchase an STI is to experience true rally car performance in a street-legal sports car. While similar in styling, the WRX STI and WRX share just a few minor suspension pieces under the skin. The WRX STI delivers a race-bred transmission, driver-adjustable differentials and Subaru SI-Drive, to name just a few. It provides a unique blend of power, grip and handling in a vehicle that delivers daily driver versatility."

We're told Fuji Heavy Industries, Subaru's parent company, is conducting its own tests to verify our results.

The Take-Away
Our tester — outfitted with the Limited package (leather and a moonroof) and navigation system — rang up a total of $39,870 including destination fees. That's $8,150 more than a similarly equipped WRX Limited.

At the end of the day the 2011 Subaru WRX STI is still a capable car. There's a genuine sense of control when driving it hard, it rips out of slow corners with enough authority to detach your retinas and the fact that it can now be had as a sedan only adds to its appeal.

Equally as important, it's still fun — an engaging driving tool that's at home on most any surface. There's lots of car here. But the question remains: Why is it less car here than before?

The manufacturer provided Edmunds this vehicle for the purposes of evaluation.