MotorTrend

Subaru BRZ tS First Drive

No Additional Power, but No Hysteresis Either
Writer

If you've been holding your breath for the Subaru BRZ to get a turbocharger or some kind of power bump, it's time to exhale. It ain't coming. We put your request directly to Subaru's top brass in Japan, and it went over like asking for ketchup at a sushi bar. The response was polite but firm: Please enjoy the BRZ's lightweight feel, front-engine/rear-drive balance, and 200 naturally aspirated horses. If you would like extra sauce, a BRZ with a healthy dollop of chassis wasabi is coming to America.

Yes, Subaru will soon sell a version of the BRZ patterned after the Japan-market BRZ tS, a limited edition that quickly sold out its initial run of 500 units, in the U.S.

The tS designation stands for "tuned by STI," which is Subaru Tecnica International, the brand's performance division. The moniker is still being debated for use in America, but in Japan, tS meant a BRZ that received a long list of hardware tweaks that read like standard tuner upgrades, including a cat-back exhaust, carbon-fiber rear spoiler, front chin spoiler, and 18-inch Enkei alloy wheels wrapped in Michelin Pilot Sport tires. Brakes were upgraded to larger-diameter rotors and four-piston front and two-piston rear calipers, all by Brembo but branded STI. Also branded STI: a whole bunch of interior upgrades, including aluminum sill plates, a red ignition button, Recaro sport seats, a leather-wrapped steering wheel, and a special shift knob.

Our version likely won't get all of these STI badges or extra goodies such as the larger-diameter driveshaft, but we should get the tS' upgraded dampers and curiously flexible chassis braces. If you find the terms "flexible" and "braces" incongruous, you're not alone.

Fans of the tuner scene will immediately notice the issue: Linking the top of the tS' front suspension towers is what appears to be a standard strut tower bar, except that instead of one rigid member spanning the engine bay there are two solid shafts connected by a spherical bearing hidden under a protective sleeve. When not bolted to the vehicle, this brace flops around in a most un-brace-like fashion.

Under the car, it gets even weirder. Just behind the engine, two "flexible draw stiffeners" solidly connect both sides of the front crossmember to the body. Or maybe semi-solidly is more accurate because while these draw stiffeners resemble rigid tie rods, they actually telescope a bit under load.

Per Yoshio Hirakawa, the head of STI, the goal of all the newfangled mods is "zero hysteresis driving" -- that is, less steering lag and a more linear response from the car. Additional goals include increased high-speed stability and a flatter, smoother, and quieter ride.

How is all of this possible? Some of the applied technology makes sense. Hysteresis is the lag between when the steering wheel of a vehicle is turned and when the vehicle actually begins to turn. Reducing hysteresis has been achieved in sports and race cars by increasing body rigidity via traditional braces and stiffeners. Slop in the chassis from soft springs and rubber bushings can be lessened via harder durometer substitutes, including solid mounts or metal spherical bearings (which the tS also has in the rear suspension linkage). These provide little to no give whatsoever but then introduce other problems, chiefly harsh ride quality, as road vibrations have nowhere to dissipate but up through the seat, steering wheel, and ultimately the driver's fillings.

This is where the innate flexibility of the BRZ's chassis and the controlled flexibility of the tS parts seem to work together. STI engineers explained that the flexible strut tower brace and draw stiffeners promote rigidity only in certain directions. The spherical bearing equipped strut tower brace apparently adds structural support across the shock towers for great steering response while also allowing for a bit of vertical movement that is key for maximum tire contact, and a smooth ride. Same goes for the draw stiffeners mounted to the undercarriage; tension within the shafts keeps the wheels running true, even under loads that would cause unbraced wheels to lift or deflect. If it sounds too good to be true, you're not alone; our technical gurus Frank Markus and Kim Reynolds remain thoroughly unconvinced until a clearer explanation or test vehicle can be provided.

That being said, I had the honor of driving a standard Japanese-spec BRZ and the tS around Japan's legendary Suzuka Circuit and can confidently say that whatever STI is doing works well. Really well.

The tS feels noticeably more planted -- as though it is more susceptible to Earth's gravitational pull. It enters and exits corners with greater confidence, precision, and clarity than the stock BRZ, which is impressive as STI claims to have left the electric power steering system untouched. They did expand the limits of the tS and revise the Vehicle Dynamic Control logic to permit more yaw before stepping in.

The overriding sensation through the steering wheel is that of tires more firmly in contact with the road, and that surely must be the case as the 18-inch Michelin Pilot Sports are 1 inch larger in diameter, a bit wider, and made of a sportier compound than the Michelin Primacy tires they replace.

It is admittedly tough to discern what the flexible chassis upgrades are contributing to the substantially better driving dynamics of the tS since the car has so many other enhancements to filter through. Is it the new Recaros, which provide the sensation of better road-holding ability, or is it the wing providing additional downforce? And is the smoother, quieter ride due to the upgraded dampers or tires or funk-master-flexing chassis mods, or all of the above?

My time with the tS at Suzuka was too brief to get that specific, but the net result is promising. The tS is certainly the best-handling BRZ ever and probably the best of the platform triplets (including the Scion FRS and Toyota GT86). Should it arrive in America with similar specifications in 12-18 months, as Subaru promised, we look forward to a comprehensive shakedown of all the new hardware. Stay tuned.

Keep reading, to get the full scoop on what's next for STI.

Still upset the BRZ is not getting more power? Get over it. The reasoning is sound. Subaru of America has been on a record tear over the last decade, going from sales of 196,002 in 2006 to more than 513,693 in 2014. This growth outpaced the entire industry, particularly during the great recession, and was built on smart investments in volume sellers such as the Outback, Forester, and Impreza -- not niche-on-niche products such as a BRZ turbo.

The good news is that SOA's rapid growth means more performance products for the U.S. Parent company Fuji Heavy Industries looks favorably on the American market, particularly as a place to grow the Subaru Tecnica International brand.

Going forward, STI will concentrate on three pillars. The first is complete vehicles, which fall into two categories: complete cars that receive horsepower and handling upgrades such as the limited-edition Impreza WRX STI S206 that was only released in Japan and Europe, and "tuned by STI" models such as the BRZ tS that receive handling and visual upgrades only. The second pillar is performance parts, which will be developed in-house, in Japan, by STI, not by contractors working under the direction of SOA (as is the case with Subaru Performance Tuning parts, which will eventually fade away.) The third and final pillar is the motorsports operation, which focuses on three categories: SuperGT racing in Asia, the Nürburgring 24 Hour endurance race in Germany, and the Global Rally Cross circuit, which runs in America and Europe.

The hope is that STI will soon start sending America its highest-performing cars and parts for enthusiasts and racers alike.

Edward Loh

I used to go kick tires with my dad at local car dealerships. I was the kid quizzing the sales guys on horsepower and 0-60 times, while Dad wandered around undisturbed. When the salesmen finally cornered him, I'd grab as much of the glossy product literature as I could carry. One that still stands out to this day: the beautiful booklet on the Mitsubishi Eclipse GSX that favorably compared it to the Porsches of the era. I would pore over the prose, pictures, specs, trim levels, even the fine print, never once thinking that I might someday be responsible for the asterisked figures "*as tested by Motor Trend magazine." My parents, immigrants from Hong Kong, worked their way from St. Louis, Missouri (where I was born) to sunny Camarillo, California, in the early 1970s. Along the way, Dad managed to get us into some interesting, iconic family vehicles, including a 1973 Super Beetle (first year of the curved windshield!), 1976 Volvo 240, the 1977 Chevrolet Caprice Classic station wagon, and 1984 VW Vanagon. Dad imbued a love of sports cars and fast sedans as well. I remember sitting on the package shelf of his 1981 Mazda RX-7, listening to him explain to my Mom - for Nth time - what made the rotary engine so special. I remember bracing myself for the laggy whoosh of his turbo diesel Mercedes-Benz 300D, and later, his '87 Porsche Turbo. We were a Toyota family in my coming-of-age years. At 15 years and 6 months, I scored 100 percent on my driving license test, behind the wheel of Mom's 1991 Toyota Previa. As a reward, I was handed the keys to my brother's 1986 Celica GT-S. Six months and three speeding tickets later, I was booted off the family insurance policy and into a 1983 Toyota 4x4 (Hilux, baby). It took me through the rest of college and most of my time at USC, where I worked for the Daily Trojan newspaper and graduated with a biology degree and business minor. Cars took a back seat during my stint as a science teacher for Teach for America. I considered a third year of teaching high school science, coaching volleyball, and helping out with the newspaper and yearbook, but after two years of telling teenagers to follow their dreams, when I wasn't following mine, I decided to pursue a career in freelance photography. After starving for 6 months, I was picked up by a tiny tuning magazine in Orange County that was covering "The Fast and the Furious" subculture years before it went mainstream. I went from photographer-for-hire to editor-in-chief in three years, and rewarded myself with a clapped-out 1989 Nissan 240SX. I subsequently picked up a 1985 Toyota Land Cruiser (FJ60) to haul parts and camera gear. Both vehicles took me to a more mainstream car magazine, where I first sipped from the firehose of press cars. Soon after, the Land Cruiser was abandoned. After a short stint there, I became editor-in-chief of the now-defunct Sport Compact Car just after turning 30. My editorial director at the time was some long-haired dude with a funny accent named Angus MacKenzie. After 18 months learning from the best, Angus asked me to join Motor Trend as senior editor. That was in 2007, and I've loved every second ever since.

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