2018 Subaru WRX STI

The Subaru WRX STI is kind of like that extremely smart kid who brings home report cards with Cs and Ds littering the page. Unchallenged, he or she gets bored, strays from the path of caring, and produces uninspired results. Offered more strenuous and demanding tasks, however, the student applies themselves and excels.

The STI is built to be pushed. It begs for tight corners, high speeds, and full throttle openings. When the driver’s blood boils, the car proves proficient. But there are broader expectations for cars with four doors and a normal trunk. Part of the STI’s charm is that it also could be a practical vehicle, even for families. It’s derived from the previous-generation Impreza, after all. But like that bored kid in class, its manners and attitude in ordinary circumstances leave room for improvement. Subaru promises a Type RA variant with performance enhancements later in this model year, but we’re not looking for an all-new next-generation WRX and STI until 2020.

The Same but Differential

Mild updates for the 2018 model year alter how the WRX STI looks and how it drives. In addition to a cleaner, more aggressive front fascia, the STI adds adaptive LED headlights, brackets for a roof rack, and dark gray 19-inch alloy wheels wrapped in 245/35R19 Yokohama Advan Sport V105 tires. It also gets a new STI Sport Design instrument cluster with a color LCD display, heated exterior mirrors, red seatbelts, a folding rear center armrest with cup holders, and a more capable security system.

The big news, though, is that Subaru fiddled with the all-wheel-drive system. Where the center differential in the 2017 STI was controlled via mechanical and electronic methods, the 2018 has gone full digital. Subaru calls it the Multi-Mode Driver Controlled Center Differential (DCCD), and it’s intended to improve the car’s already great handling. Subaru also upgraded the brakes, using yellow-painted monoblock Brembo calipers, six-piston up front and two-piston in the rear, as well as larger cross-drilled vented discs, 13.4-inch in front and 12.8-inch in the rear.

Our test car was the base STI. For another $4800, the STI Limited adds nothing performance-oriented but packs in the features, including a power sliding sunroof (which chops front headroom by 2.6 inches), proximity key, push-button start, navigation, a Harman/Kardon audio system, blind-spot detection with cross-traffic alert, and eight-way power-adjustable Recaro performance seats. (Our test car had the Recaro seats, a $2500 option bundled with the proximity key and push-button start.) The STI Limited also presents the option for a lower-profile decklid spoiler instead of the standard STI wing. Buyers in need of even more safety-oriented driver assists should lower their sights from the driver-centric STI and consider the regular WRX Limited, instead.

Sucker for Pain

The mid-cycle update for the WRX STI sadly did not bring any changes to the aging powertrain. While the standard WRX has a 268-hp turbocharged 2.0-liter flat-four, the STI has a turbocharged 2.5-liter that is not used in any other Subaru. It makes the same 305 horsepower at 6000 rpm and 290 lb-ft of torque at 4000 rpm as last year’s model, which is only 5 ponies more than the 2004 STI had on tap. (Even the RA special edition coming early next calendar year is rated at only 310 hp.)

It also comes equipped with SI-Drive (or Subaru Intelligent Drive), essentially a drive-mode selector that only affects the engine’s power delivery. Using a center-console dial, drivers can pick among Intelligent, Sport, and Sport Sharp, depending on whether throttle response or fuel efficiency is more important. When switched into Sport or Sport Sharp, a torque curve is displayed in the center screen. Basically, each step up the ladder delivers more torque for a given movement of the accelerator pedal.

Putting the engine to work requires an active right arm and accepting that every day is leg day in STI-land. The clutch pedal effort feels like resistance-band training as it takes plenty of push. The engagement point on the test car was high in the pedal travel, making it tough to engage without lurching, and the shifter itself doesn’t really aid in making smooth progress in traffic. It all comes together better when you’re moving at full chat, but it becomes a chore that demands more attention than it ought to when you’re simply trying not to upset passengers.

When testing the previous STI, we experienced wheel slippage during hard launches, but that wasn’t the case with this car. It seemed to be somewhat down on power to a degree that forced us to attempt our acceleration tests with three different drivers. Even with the car set to Sport Sharp mode, we could not break the five-second mark to 60 mph, finally accepting 5.3 seconds as the best it could do. The STI we tested two years ago, which was wearing Dunlop Sport Maxx tires and weighed about 50 pounds less than this 3451-pound example, ran from zero to 60 mph in 4.8 seconds with a redline clutch drop. With less horsepower and a smaller price tag, our long-term 2015 WRX manual hit 60 mph in 5.0 seconds flat, and the 2018 WRX with a manual needed 5.5. We’re calling this one an anomaly.

Stopping from 70 mph the Brembo brakes perform as expected, dragging the car to a halt in only 158 feet, but even that good figure was a couple of feet longer than the 2018 WRX without the STI enhancements.

Deft control on challenging roads is where the STI lives up to its potential, with firm body control and fine balance. Although a little nervous on-center, the steering is quick, well-weighted, and communicative. In place of the regular WRX’s electrically assisted power steering, the STI uses hydraulic assist and a quicker ratio (13.3:1 vs. 14.3:1).

Beneath the SI-Drive dial is a button labeled Auto/Manu and a switch labeled C.Diff. In the Manual setting, this is a control unit that allows the driver to choose the torque bias on the all-wheel-drive system from six distinct differential-locking setups. In Automatic, it delivers 41 percent of torque to the front axle and 59 to the rear, but can alter that as circumstances demand. Up front, the STI has a helical limited-slip differential while the rear has a Torsen unit, and all WRXs have brake-based active torque vectoring. Traction and responsiveness are this car’s strong suit, on both paved and gravel roads.

Although the stiff suspension makes for a rougher ride than you’d find in newer competitors such as the Volkswagen Golf R, the car is nothing but composed when pushed hard. However, while the Subie showed little to no understeer at the handling limit, the modest 0.93 g it registered on the skidpad falls well short of the Ford Focus RS’s 1.04 g and the Honda Civic Type R’s 1.02 g of lateral grip.

That single metric portrays the broader story of where this car sits amongst its new-age peers. Gone are the days of the fiery STI versus Mitsubishi Evo all-wheel-drive sedan rivalry. The WRX STI faces better-rounded competition from the 350-hp Focus RS (although that car’s hoontastic character has its own flaws), 306-hp Civic Type R, and the Golf R. The STI ranked third in a three-car comparison against the Ford and VW, but it still is great fun. It’s just that the competition has outpaced it, with similar or even lower base prices, more refinement, and better-looking interiors.

One saving grace, for now, is that the RS and Type R are limited-availability cars for which dealers are charging steep premiums over their list prices. What doesn’t help is that the regular WRX’s performance is not that far off the STI’s, and it allows more options. That Subaru did away with the STI’s hatchback body style also displeases many enthusiasts. Subaru fans who have longed for an STI are unlikely to be disappointed by this one’s rally-bred character. However, that the STI’s rivals are more refined and perform better tells us that Subaru needs to hit the books for an updated sport-compact degree.

Specifications >

VEHICLE TYPE: front-engine, all-wheel-drive, 5-passenger, 4-door sedan

PRICE AS TESTED: $39,455 (base price: $36,955)

ENGINE TYPE: turbocharged and intercooled DOHC 16-valve flat-4, aluminum block and heads, port fuel injection

Displacement: 150 cu in, 2457 cc
Power: 305 hp @ 6000 rpm
Torque: 290 lb-ft @ 4000 rpm

TRANSMISSION: 6-speed manual

DIMENSIONS:
Wheelbase: 104.3 in
Length: 180.9 in
Width: 70.7 in Height: 58.1 in
Passenger volume: 97 cu ft
Trunk volume: 12 cu ft
Curb weight: 3451 lb

C/D TEST RESULTS:
Zero to 60 mph: 5.3 sec
Zero to 100 mph: 13.0 sec
Zero to 130 mph: 26.1 sec
Rolling start, 5–60 mph: 7.0 sec
Top gear, 30–50 mph: 12.3 sec
Top gear, 50–70 mph: 9.1 sec
Standing ¼-mile: 13.8 sec @ 102 mph
Braking, 70–0 mph: 158 ft
Roadholding, 300-ft-dia skidpad: 0.93 g

C/D FUEL ECONOMY:
Observed: 20 mpg
75-mph highway driving: 25 mpg
Highway range: 390 miles

EPA FUEL ECONOMY:
Combined/city/highway: 19/17/22 mpg