Though the immaculate exterior might not suggest it, this 2006 Subaru WRX STI has wandered a long and sinuous path since its current owner, Shane Besharaty, got his hands on it some five years ago. It started its term with him as a lightly modified road car, and it has been with him every step of the way with him since he’s transitioned from backroad hooligan to serious track rat. Its transformation from road car to race car reflects that lengthy journey.
It would be a mistake to assume its changed entirely from where it started. Even now, as a dedicated track car, this car remains practical and approachable. Practical might be a poorly chosen word in the context of a monster with over 500 horsepower and 9.5″ semi-slicks at each corner, but there’s enough civility avoid rattling the fillings out of Shane’s skull when he drives around Burbank.
It had to be reasonably civil, because for the first five years in Shane’s hands, it was first a street car with no circuit racing pretensions. The car was fitted with an SPT catback when he purchased it, and he quickly added a COBB Accessport, a K&N air intake, a Perrin 3″ downpipe, swaybars, and RCE Yellow springs. This modest list of modifications was perfect for canyon blitzes and Shane was content for several years. After his first trip to Buttonwillow in 2017, however, everything changed.
As a big rig driver for the motion picture industry, his license is his livelihood. Therefore, after experiencing the thrills and challenges only attainable on a circuit, he wisely decided to quit the hooligan act and convert into a responsible and committed track rat. In addition to his attitude towards driving, his car had to change to suit the new environment he chose. While the aforementioned modifications might’ve been superb for the canyons, the increased loading and abuse experienced on the track rendered them obsolete. He had to select some very choice parts to meet his aims and bring his car to the incredible state it’s in currently.
No Expense Spared
With Renner Racing Development guiding him and doing the major engine work, he started a new chapter with with a Cosworth shortblock with an 8.2:1 compression ratio, stiff Group N engine mounts, and a hefty Garrett GT3076R turbocharger. To complement the added air brought by the big snail, he beefed up the fuel system with a Walbro 450lph fuel pump, ID 1700cc injectors, and a custom surge tank.
To improve airflow, he went with a Honeywell front-mount intercooler, a 180-degree intake manifold, a Magnaflow 3” exhaust, and a Perrin 2″ up-pipe. When combustion was maximized with NGK iridium spark plugs and a safe tune from Yimi Sport, not only was the once violent power delivery rendered smooth and predictable, it offered a manageable wave of torque from 4,000-7,000 rpm. Since full boost arrives at 4,300 rpm, he’s always able to remain in the meat of the powerband; hairpins are never ruined by a bogging motor.
More than just a massive mid-range wallop, the peak figure of 437 horsepower on 101 octane kept him happy for a while, but he soon sought more. After installing an easy-to-use COBB flex fuel system, cranking the boost up to 29 psi, and filling his tank with a few gallons of fragrant E85, those numbers jumped to 487 horsepower and 463 lb-ft of torque at the wheels. For a car weighing in around 3,000 pounds, that was enough thrust to outrun some of the big-bore rivals during his last trip to Buttonwillow.
Despite dealing with gobs of grip, a wave of torque, and four driven wheels, the gearbox has handled the abuse without fuss. Granted, fourth gear did cough its last several months ago, but aside from that, it’s been nothing but smooth shifting. An ACT clutch and lightweight flywheel combination, a COBB adjustable shifter, plus a Group N transmission mount round out the rest of the additions to the gearbox. Not too extreme considering the stresses a powerful four-wheel drive car’s drivetrain must undergo.
Naturally, a turbocharged engine producing that power gives off a good deal of heat. To keep his engine bay from becoming a very expensive barbecue, he wrapped the Garrett’s turbine in a PTP turbo blanket, added a Setrab oil cooler, replaced the factory radiator with one from Koyorad, and installed several vents in the hood. Even on a roasting Los Angeles afternoon in August, the EJ25 runs cool.
A stout motor with all the fixings in his possession was cause for celebration, and the performance wasn’t bad either. The straightline speed and enough to leave Shane giggling like a kindergartner. It also left the motor stuttering in right-hand bends. A common issue with the EJ25 motor at high lateral loads is fuel starvation, so Shane remedied this with a surge tank and a second fuel pump.
Sharpened for the Circuit
While the factory RCE springs were compliant enough for California roads and supportive enough for the occasional jaunt through the canyons, the car fell on its face on the racetrack. With the help of West End Alignment, Shane starting piecing together a kit that would serve his purposes and not cause too much headache.
“I prefer to spend a little more the first time around, because being too tight-fisted usually just ends up frustrating me; eventually, I’ll have to get the right item. Why not do it at first?” he establishes. With that in mind, he splurged and picked up some of the best for his purposes: a set of JRZ RS-Pro two-way coilovers fitted with Hypercoil springs. With external reservoirs mounted inboard, he’s able to maintain his suspension performance over the entirety of a frantic twenty-minute session regardless of the bumps or the ambient temperature.
Even with pricey additions, he’s realizing that the current setup might not be enough for his needs. With 500-pound springs and 550-pound springs front and rear, respectively, his suspension is beginning to show its limitations. “It’s actually a little too soft,” he begins, “since it’s maxing out compression, and I’m nearly maxed out with the rebound.” New springs are on the horizon, but he’s wisely waiting for a few new aero pieces to be installed before determining just how much spring he’ll need.
Fortunately, there are plenty of items which are more than sufficient for the time being. A Beatrush front subframe helped sharpen turn-in, and Whiteline anti-lift kit keeps it squat under longitudinal loading. A common problem with this car is to lift the inside front wheels slightly under acceleration and cause some hopping. With the anti-lift kit, as well as a complete set of Cusco differentials, the wheel hop was almost completely eliminated.