If the Suzuki SX4 hatchback — one of the most overlooked small cars out there — has one flaw, it's a lack of giddy-up. While its stock 143 horsepower is higher than output numbers for the Nissan Versa, Honda Fit, and Toyota Matrix, it isn't enough to go out and win a weekend autocross, no matter how horribly the other guys drive their WRXs and GTIs. Thank goodness that somewhere between the seventh day and today, God created turbochargers.

The SX4t is a one-off concept based on the SX4. The most pertinent difference? It's been blessed with forced induction. Its turbocharger, a Mitsubishi 16G GT3 with a Tial 38-mm wastegate, comes courtesy of Road Race Motorsports of Santa Fe Springs, California. Along with an intercooler and exhaust, its seven pounds of peak boost bring the SX4's 2.0-liter up to 221 hp and 208 lb-ft of torque on premium fuel. Power delivery is more like a tuner special than what we've come to expect from production turbo cars, with boost that's slow to build before swinging its torque hammer down on the pavement with an ear-ringing whoosh of air.

Fortunately, staying on boost isn't a problem on the four-mile course at Road America, where we tested the little beast. Even through the track's 90-degree brake heaters at turns five and six, getting back on the power early keeps the SX4t screaming. More impressive is that on a day where a Mustang Bullitt test car goes all soft in the middle pedal early on, the SX4's stock rotors and Road Race performance brake pads show little signs of fade, though we still crave a bit more stopping power: Though the brakes remain consistent over time, they don't bite down with verve, and they are not of a piece with the car's sub-seven-second 0-60 acceleration. While this car was in the Road Race garage, Suzuki should have asked for a set of the company's $1800 Rotora brake system, which features four-piston calipers and 13-inch rotors.

Other than a set of Road Race GRIP springs, the SX4t's suspension is also stock, though the wheels and tires have been swapped out for Rota five-spokes and 225/45R17 Yokohama Advan Neovas. A few laps at full bore reaffirm our praise of the Suzuki's neutral all-wheel-drive chassis, which is predictably biased toward understeer but never plows. Body roll is a bit excessive, but if Suzuki were to build a production hot hatch it would surely get a more thorough stiffening of the suspension.

Because it retains so many stock components, the SX4t isn't a complete transformation from its tamer counterpart. Think of it as a Mazda3-to-Mazdaspeed3 evolution, not a Cobalt LS-to-Cobalt SS revelation. The power is much better, but the steering, the suspension, and the brakes are all just slightly enhanced. It's a good aftermarket effort that could use Suzuki's full engineering resources to make a real surprise performer. It wouldn't take much more — just some larger brakes and a few ratchet cranks down on what's already a good chassis.

Road Race has even already cleaned up the car's outer appearance. The vented carbon fiber hood (an $800 part from CarbonTrix) is an acquired taste, but the car's project team did a fine job with the rest of the little 'Zuk, eliminating the roof rack and plastic cladding along the wheel housings. The turbocharger kit, which goes on sale this summer, will run $5400 while the sport springs cost another $240. Making a production run of SX4t hatches would drive those prices down so that Suzuki could potentially offer the car at a price just under $20,000. It would make a neat alternative to the VW GTI, Mazdaspeed3, Chevy HHR SS, and a gang of other ruffians with stickers all around $23,000 or more. That price margin could drive the SX4's role from "overlooked" to "best performance bargain out there." And that sounds pretty good to us.