Subaru Impreza WRX STi reviews

Subaru Impreza WRX STi Driving Impressions

In any of its many guises, the Subaru Impreza is a solid performer. All but the ultra-high performance WRX STi are comfortable, easy to live with, and quite practical. Any Impreza is very stable and forgiving, thanks to its all-wheel-drive system, which improves both performance and all-road capability and in certain respects adds a margin of safety.

Imprezas have always been fun. What stands out in the 2006 models is how refined it has become. It's almost as if years of incremental improvement have somehow reached critical mass and moved Impreza up a level or two. Particularly with the WRX, the Impreza makes its case with sophistication as much as thrills for the buck, the way the best small European cars do.

No doubt Subaru's Ring Frame Reinforced body helps. That's what the company calls the underlying structure, which now uses hydroformed sections and components stamped from tailored blanks. Those techniques have one key advantage: more strength and rigidity without an undue increase in weight. You might think of RFR as a safety cell in roughly a cube shape around the passenger compartment, and Subaru's primary objective is better occupant protection. Yet the structural improvements pay dividends in many ways, like more responsive handling, better ride quality and improved smoothness in just about every aspect of the Impreza's operation.

For 2006, the base Impreza engine has been massaged with new technology, including an electronic (drive-by-wire) throttle and variable valve timing and lift. This 2.5-liter four cylinder retains Subaru's familiar horizontally opposed cylinder design. The boxer, as it's called, was the engine design used in the original Volkswagen Beetle, and it's still used in Porsche's sports cars. The improvements to the Impreza engine increase horsepower on 2006 models by eight to 173 hp. By that figure, the Impreza 2.5i leaves competitors like the Mazda 3 and most Honda Civics in the dust.

Those familiar with a boxer engine will recognize the faint, loping vibration that makes its way through the flywheel and down the center of the car at idle. It's comforting to anyone who's owned an original Beetle (or 911). The other thing about boxers, compared to some inline four-cylinder engines, is an abundance of acceleration-producing torque at low- to mid-range engine rpm. Here the Impreza 2.5i has it all over most of its competitors, generating an impressive 166 pound-feet. And there's an added benefit to this good low-end response. In the past we've found the Impreza better suited than many four-cylinder cars to an automatic transmission. Acceleration is brisk, and thanks to the new variable valve operation, the 2006 Impreza 2.5i is more flexible than its predecessor. The engine breathes a little better than before at high rpm, and it keeps pulling strong further up into the rev range.

The 2006 Impreza WRX gets even more extensive improvements than the 2.5i, and a new engine entirely. Until now, the WRX was equipped with a smaller, 2.0-liter version of the boxer, powered up with a high-boost turbocharger. Now it gets the 2.5, still with a turbo and intercooler. Horsepower has increased by 13 to 230 hp; at least as significantly, torque increases by 18 to 235 pound-feet.

Along with the engine, the WRX gets aluminum suspension arms front and rear (as do some very expensive cars). The steering ratio is even quicker than before. The brakes, already large for this class, now have four-piston calipers in front. It's serious stuff, and should dissuade anyone who might still think of Impreza as an economy car.

The best news: the WRX may be more fun than ever. Some may lament the passing of the higher strung 2.0-liter engine, but the 2.5 is more mature. It feels more substantial at all speeds. It still makes revs quickly, to the point that under hard acceleration you might bump the rev limiter before you realize it's time to shift up. B