Along with the stock internals and valvetrain, the WRX's driveline is virgin territory. The suspension is a different story.
Perrin hit its parts bin and found the WRX/Legacy 2.5 GT front anti-roll bar and end links, as well as Legacy 2.5 GT control arm bushings, were straight swaps. Due to the brand new double-wishbone rear suspension design, Perrin had to design a new rear anti-roll bar and made the prototype with three different mounting holes to allow for adjustment in stiffness.
For added damping, Perrin called H&R, which supplied a number of prototype coilover kits to try. Being so new, there weren't any model-specific set-ups, so, in essence, Perrin kick-started H&R's research and development. The results gave Perrin full command of the adjustment of damping, spring rate and ride height, which proved key at the track, where the WRX struck fear into the competition as it transitioned through the twisties.
A set of 17x7.5 Konig Feather wheels, which weigh a scant 17 pounds each, are wrapped in Yokohama Advan Neova tires. The car runs 245-width tires, but Perrin reports that 255s should fit-with some coaxing of the fenders.
The 2008 WRX is rated at the same horsepower level as the outgoing car, which may be troubling when its main competition, the Lancer Evolution, has advanced in almost every category. However, the WRX's $24,850 base MSRP is well under the Evo X's projected price of $30,000. This is a crucial point for those who spend softly, but still like to carry a big stick with aftermarket upgrades.
2008 Subaru Impreza WRX
Engine
Engine Code: EJ25
Type: 2457cc, horizontally opposed four, aluminum block and heads, turbocharged and intercooled, DOHC, AVCS variable cam phasing
Internal Modifications: Stock
External Modifications: Perrin Performance GT3071R rotated-mount turbocharger kit, air intake, front-mount intercooler kit, up-pipe, header, three-inch downpipe, high-flow catalytic converter, stainless steel exhaust system
Engine Management Modifications: Perrin fuel rails, 816cc/min fuel injectors, Walbro 255lph fuel pump, Hydra ECU
Drivetrain
Layout: Longitudinal front engine, all-wheel drive
Drivetrain Modifications: Stock
Suspension
Front: H&R coilovers, Perrin anti-roll bar, end links, control arm bushings
Rear: H&R coilovers, Perrin adjustable anti-roll bar
Brakes
Front: Stock
Rear: Stock
External
Wheels: Konig Feather, 17x7.5
Tires: Yokohama Advan Neova, 245/40/17
Body: Stock
Interior: Stock