Giving It L – GST Motorsports’ World-Beating 1996 Subaru Impreza L Began its Racing Career in NASA

Today many of the world’s fastest cars do not trace their lineage from the winner’s circle back to the showroom floor. John Force’s Mustang is anything but. Lewis Hamilton’s McLaren MP4-27 was by no means converted from an MP4-12C, and the Poteet & Main Speed Demon Streamliner looks like it should be carrying Curiosity to the red clay of Mars instead of George Poteet across the white salt of Bonneville. Whatever happened to the days when a manufacturer would build a Superbird for a King or a plucky chicken farmer from East Texas could go to France to beat up on Enzo?

Those bygone days of sell-on-Monday-strip-build-and-race-on-Sunday are still very much alive for Mike Warfield and his GST Motorsports team. Warfield embodies the can-do spirit of a Petty or a Shelby, which is somewhat ironic since he was born in England (Frimley Park Hospital in Surrey to be exact) before emigrating from the U.K. to Northern California in 1999. Warfield’s 1996 Subaru Impreza L is the manifestation of this spirit as the car currently holds no less than seven separate overall time attack track records across the United States.

Time Attack, specifically the Global Time Attack is where GST’s L has set most of its records. Global Time Attack is sanctioned by NASA, which also handles the tech, timing and scoring for this series. The sport of time attack originated in Japan with one car against the clock as a way for aftermarket tuning shops to prove their worth. Think of it as a time trial turned up to eleven and shot full of steroids with a Red Bull chaser. In the Unlimited Class, where the GST L does its damage, the minimal rules require little more than a car that must be based on and maintain the appearance of a production vehicle. The only restrictions are the exclusion of silhouette cars and tube chassis conversions, but most important to the teams and fans, there are no equivalency formulas that neuter the cars in the name of fabricating close competition.

GTA’s open rulebook appeals to the GST front man who says, “I like being in the Unlimited Class, which enables us to be creative with items like aero and powertrain. Obviously nowadays there are some seriously funded cars in our class but that just makes it more fun for us when trying to wring out that last tenth of the car.”

You’d be forgiven for thinking Warfield’s L has little in common with its showroom stock counterpart because its appearance is even more menacing than Flounder’s brother’s 1964 Lincoln after it was Death Mobile’s by the Delta Tau Chi fraternity (kids, ask your parents). Believe it or not this sinister Subaru was Warfield’s daily driver before being pressed into service as a NASA racer.

As with all great stories, Warfield’s affair with his L began in a hotel room with a wad of cash. Freelance work for a medical company brought Warfield to Seattle in late ’03. “I flew up to Seattle, worked 36 hours straight and I was left with a bunch of cash in my pocket and a return flight some 48 hours away,” Warfield recalls. “I sat in my hotel room bored and while surfing Subaru forums came across a local guy selling a 1996 Impreza L coupe with a 1999 RS engine swap. I contacted the seller, checked out the car and agreed to a deal. I drove the car home overnight and it became my daily driver. And as with most great racecar stories, daily drivers don’t get driven daily for long.

“While working for Gruppe-S, I was chatting with the Lock family about building something for NASA’s 25 Hours of Thunderhill,” Warfield said, “when attention turned to the little L sitting in the parking lot and a decision was made to build it for the 2006 race.

“The car qualified fourth, but we soon discovered we needed more than a quick car for a 25-hour event and after about the second hour we started breaking things ranging from wheel bearings to turbo up pipes,” remembers Warfield. “We managed to cobble something together to limp the car over the finish line. The drivers that year were Brian Lock, Mike Lock, JG Pasterjak, Christian Miller and Chris Lock.”

After reading about time attack in various import tuner magazines, Mike and his team thought it would be fun to give it try for themselves. After a simple tire change and an increase in boost the car’s first event was at the 2007 Redline Time Attack season opener at Buttonwillow Raceway. With Brian Lock driving the L finished second overall and first in class.

After this it was off to the races, so to speak. The little L has gone through a spate of evolutionary changes over the years most notably to the exterior. Light weight and aerodynamics are key to time attack records and GST’s Subaru meets both of these criteria right out of the box. The Impreza’s nose creates less frontal area than the more snub-nosed WRX and the curb weight is far less than late-model Subies.

From here Warfield and crew set to work on making the L wider with broader fenders. This allows for the fitment of the 18×11 Rota MXR wheels (in a +20 offset). Wider wheels mean bigger meats for more contact patch and the L features Continental’s R80 slick, sized 305/645R18. Other tricks include a chopped top (to further reduce weight and drag) and a flat bottom floor with a rear diffuser. Most of the bodywork is custom save for the Kognition Design rear wing and the paint is rattle can black, which perfectly matches the team’s humble roots.

With all of the aero at work, downforce is increased, which is great for mechanical grip but just terrible for drag. The less “slippery” a car is, the harder the engine must work to achieve speed. This is where another key time attack component comes into play – raw power to help this high-drag Subaru punch through the air.

Warfield is a self-taught tuner who, at the urging of his wife Dionne, went into business for himself as a Subaru specialist. Mike’s knowledge has served him well as the L’s EJ257 powerplant makes some 725 whp from 38 pounds of boost from a single Garrett GTX2582 turbo. Darton Sleeves by Race Engine Development shore up the block while JE FSR pistons are domed for a 9.0:1 compression ratio and hung on Brian Crower rods and a billet 79mm crank. Up top the hits keep coming with Brian Crower cams while Cosworth supplies the valves, springs, retainers and intake manifold. The Garrett slug hangs on a Full-Race manifold with two of Turbosmart’s Comp Gate 40 wastegates and a Race Port blow-off valve. Warfield controls the works with a Hydra Nemesis engine management system and it runs on E85, making this Subie green. Sort of.

Some say it takes a Chuck Yeager mentality to drive one of these Unlimited Class time attack cars as their builders are constantly plotting ways to go faster sometimes in an almost experimental fashion. To break records, a driver needs skill, speed and, well, stones to get the most out of these machines. GST has found their man in Jeff Westphal, an accomplished Grand-Am shoe and F2000 Champion. It’s safe to say Westphal has a little Yeager in him.

Any GTA drivers who find themselves in front of Westphal and GST’s Subaru should realize two things: First, you are sharing the track with one of the world’s fastest cars. Second, you should probably get the L outta the way because this scrappy little Subaru means business.