WRX Total Tuning Tech

Stating that the Impreza WRX has taken the performance world by storm would be making a gross understatement. Upon its arrival in 2001, enthusiasts who had been sitting on pins and needles anticipating its long overdue coming finally had their dreams of boost come true. Sure, it may not have been a full-tilt--boogie JDM STi, but for its suggested retail price of less than $25,000, nothing else on sale in North America could touch its performance credentials for the money.

Mark Miller, a die-hard car nut and owner of Westminster Speed and Sound of Westminster, Md., was one of those early buyers who had been praying for pressure. By a stroke of good fortune, Miller ran into Brett Middleton, proprietor of Middleton Rally Team, or MRT.

MRT has long been one of the premier WRX tuners in Australia, offering a bewildering array of speed parts for the car, and with the introduction of the WRX in America, it was looking for outlets stateside through which it could offer its goods. Talk about a match made in heaven.

Miller enthusiastically struck a deal with MRT to become an authorized u.s. distributor. Naturally, Miller's newly acquired WRX went through a whirlwind eight--week transformation to become a showcase for MRT upgrades and illustrate how. easy it is to make a tuning impact on all aspects of the Scoobie's performance.

The first noticeable thing about the stock North American-spec WRX is its wheel and tire package is pitifully weedy. Those little 16-inchers look lost beneath the WRX's bulging fenders, and the tires' 205mm section width seem a bit skimpy considering the power available from the engine.

Miller's first order of business was to find suitable replacements. The stock wheels were replaced with far more aggressive forged 18-inch Center Line RPMs, notable for their strength and lightness at an affordable price. The wimpy stock Bridgestone Potenza RE92S were pitched in favor of sticky P225/40ZR-18 Michelin Pilot Sports.

This aggressive wheel-and-tire combo upped the car's handling prowess considerably, but as this car wasn't headed for any rally stages in Kenya, the suspension could be set up for aggressive tarmac use.

The stock springs and struts were replaced with a DMS Gold 40 coil-over setup, providing much stiffer springing and damping as well as allowing adjustment of the car's ride height. After some tinkering, Miller decided to drop the car's ride height 1.6 inches providing a lower center of gravity as well as a more menacing stance. Subaru STi front and rear strut tower braces were bolted in to further enhance the WRX's already stiff chassis.

Finally, Whiteline 22mm front and rear sway bars and anti-lift kit (this increases positive castor at the front for improved turn-in) rounded out the chassis mods. Of course, a car with such a serious chassis setup requires brakes to match, so StopTech's 13.1-inch big brake kit was called upon to provide the needed stopping power.

Since the chassis' capabilities were suitably raised, attention could now be turned to the engine. After all serious power upgrades on the stock suspension would create a seriously unbalanced beast, but with the chassis now dialed-in, the car was ready for more power -much more.

As Subaru enthusiasts know, the EJ20 flat-4 is an extremely robust unit from the factory, with internals designed to handle far more than the stock car's 227 hp. Japanese versions of the motor are rated up to 280 hp (and that's "advertised" horse-power, due to the Japanese motor industry's agreement to not advertise more than 280 horses), so the engine in North American tune is capable of handling significant power increases. As such, Miller left the engine's guts alone and elected to make power strictly with bolt-on mods.

Miller enthusiastically struck a deal with MRT to become an authorized u.s. distributor. Naturally, Miller's newly acquired WRX went through a whirlwind eight--week transformation to become a showcase for MRT upgrades and illustrate how. easy it is to make a tuning impact on all aspects of the Scoobie's performance.

The first volley of mods were fairly predictable -MRT's cold-air intake and top--mount intercooler were installed to minimize intake air temperatures, and a Go Fast Bits blow-off valve effectively purged excess boost. MRT's cat-back exhaust really helped the car wake up, allowing the engine to make meaningful boost lower in the rev range.

But the real centerpiece is the MRT TMS 3 turbo management system. More than just a boost controller, this is a complete and integrated system of components that work together to create safe and reliable horsepower. The system consists of a boost controller, boost gauge, turbo timer, voltmeter, air/fuel gauge, and rally-style water spray controller.   

The interface for this system is cleanly and cleverly mounted where the ashtray used to be. Initially, Miller played with the boost settings on the stock turbo, taking it up to about 16 psi, which he says is really the safe limit on a stock EJ20 bottom end. After all what fun is a WRX that doesn't run due to a blown engine?

Miller was fairly pleased with the results; the WRX was far quicker than stock-which is saying a lot, since a stock WRX is plenty fast to begin with. Best of all he knew he was running boost at a level that wouldn't cause undue stress to the engine's internals.

Still in Miller's mind, things weren't quite perfect. While the engine ran well, boost seemed to drop off over 6000 rpm. While the car was very driveable at moderate engine speeds, the engine lacked the high-speed urgency that Miller was looking for.

The solution? Bigger turbo, of course! Miller raided the Subaru parts bin and installed a big STi VF24 turbo. Due to the turbo's bigger size, the engine lost a bit in the lower part of the rev range. But this car isn't meant to be driven at low engine speeds. With the VF24 turbo, the WRX now pulls hard from 3000 rpm all the way to the 7200-rpm red-line. That's more like it!

As this car is a showcase for Miller's WRX business, a few neat finishing touches were necessary to complete the car. Morrette WRC-style headlamp clusters were installed, reducing the "bug-eyed" look that many Subaru enthusiasts com-plain about (and also goes away for the 2003 model year). A 22B-style wing adorns the rear decklid, adding to its rally -in spired looks.

Finally, just to be safe, an SPW fire extinguisher was mounted inside. As this car is a showcase for Westminster Speed and Sound's capabilities, even wilder upgrades are on the way. Miller's efforts have yielded a car that is impressive by any measure. It's equally impressive that this car is daily driven. That speaks volumes about the inherently solid engineering of the WRX, and the solid engineering behind the race-proven componentry from MRT. Miller's almighty Subaru embodies what a few well-chosen modifications can do to the power output, handling and aesthetics of this rally-inspired street machine.

Information and pictures of the latest stages of the WRX will be coming soon. Stay tuned.       

Westminster Speed and Sound would like to thank:

Center Line Wheels
MRT Performance
SPW, Inc.
StopTech
Turbo & High Tech Performance Magazine