The Mitsu's 2.0-liter engine honors WRC convention, but it, like the STi's, has been given a thorough going-over. The transversely mounted in-line four makes 271 horsepower and 273 pound-feet of torque and uses numerous forged pieces such as the connecting rods, aluminum pistons, and steel crankshaft for greater durability. The turbocharger feeds the engine with as much as 19.0 pounds per square inch of pressurized air, and a twin-scroll housing maintains high gas velocity for better throttle response in the face of that very large-capacity turbo. Most of the reciprocating parts in this engine have been lightened and/or strengthened over a decade of racing development, extending to the camshafts, valves, and valve cover, the latter cast in magnesium. As in the STi, a large intercooler keeps things from boiling over, and if they do, the Evo has a switch inside that will automatically spray the air-to-air intercooler with a shot of cold water as needed.
But, unlike the STi, the Evo only comes with five speeds in its gearbox and none of the fancy electronic trickery lurking in the Subaru. The Mitsubishi's driveline is comparatively straightforward, with an open differential at the front, a viscous-type limited-slip device in the center, and conventional pressurized-plate limited slip at the rear.
The differences pretty much end there. The Mitsubishi also has inverted struts up front (but multiple links in back), big Brembos with electronic brake distribution, and super-lightweight Enkei wheels on Yokohama tires that look like grooved slicks.
We snuck the STi and the Evo back over to San Bernardino, California, to a pass in the San Gabriel Mountains that would serve as our de facto rally stage. This red-sand two-lane, soaring and plummeting like a falcon riding thermals, was bent with first-gear turns and painted with thick black skid marks. As the STi and the Evo charged up and down, they whistled like teakettles.
Although the terrain was a sort of homecoming for both cars, they attacked it differently. We wondered how two cars this close in specification and purpose could feel so markedly distinct, from their power delivery to their steering, braking, handling, and ride--a surprising dynamic contrast for so tight a contest.
In the Japanese compact-sedan arms race in which these two are locked, the STi has clear ground superiority. Its nearly 30-horsepower advantage is astounding, garnering a standing ovation for Subaru at this year's Detroit show when the company announced those output figures. The 2.5-liter four growls like any boxer engine but is refined and quiet at cruising speed. It never darts to its 6000-rpm power peak; instead, forces mount evenly. Unlike with the 227-horsepower WRX engine, there is no turbo lag and just a whiff of camminess around the 4000-rpm torque peak. Throttle response is precise and instantaneous. In tightening third-gear sweepers, it's rare to feel as if you've selected too high a gear, but the gearbox's close ratios frequently have you running out of second. Changing up is no chore, thanks to positive, light-effort throws.
Still, the Evo's powertrain is far feistier. It revs more freely, barks louder, and rushes up to its redline with more urgency than Dom DeLuise being shot by a catapult toward a chocolate cake. There is an elastic quality to this engine that more than makes up for its ten percent power deficit, its throttle lag, and its slower across-the-board performance numbers. Its neck-yanking power crescendo makes the Evo feel faster than the STi, even if it pulls far fewer g's under acceleration. Shift action, too, is more immediate than the STi's, with a bolt-action assuredness.