Diggmania in Action: In the Autoblog Garage: 2008 Subaru Impreza WRX vs. STI

Click above for a high-res gallery of the Subaru WRX
Last year when the 2008 Subaru Impreza debuted at the New York Auto Show, many fans of the road-going rally car were taken aback. The older, aggressively styled four-door sedan now had a decidedly pedestrian look to it. Worse still, the cool looking mini station wagon of the previous generation had been dumped in favor of an oddly proportioned five-door hatchback. We only got to see the base and WRX versions in New York and had to wait until the Tokyo Motor Show in the fall for the hard-core STI variant. When the STI did finally appear, it had shifted from the four-door to the hatch body style. Fortunately for Subie fans, the aggressive bulging fenders and super-sized rear spoiler remained from the previous car, although the proportions still look a might peculiar.
The countdown to the inevitable EVO-STI showdown had begun. Unfortunately, you won't be seeing that battle here just yet. We did, however, have the opportunity to review a new WRX and spend a few days with an STI model only a week apart. Since we'll soon publish a solo In the Autoblog Garage review of the STI, we want to focus here on the two rally-inspired Imprezas and how they compare in day to day use.

Gallery: Autoblog Garage: 2008 Subaru WRX

Gallery: Autoblog Garage: 2008 Subaru WRX STI (Preview)

Photos Copyright ©2008 Sam Abuelsamid, Alex Núñez / Weblogs, Inc.
click any image to enlarge

Nearly a year from its debut, the WRX hatch is actually kind of growing on us. We'd still rather have the old wagon, but this one doesn't make our eyes hurt anymore. While we didn't have the two cars at the same time, it's easy to see that the new WRX looks downright plain Jane compared to its big brother. The STi looks like it spends its days at the gym while the WRX appears more like a long distance runner, slimmer and trimmer. Where previously even the base WRX had fenders that bulged like a ProDrive special, the new model shares its side body panels with the standard Impreza.

Moving inside, one quickly wonders if perhaps some of those designers responsible for recent Chrysler interiors have gone to work for Subaru. As is so often the case, the layout and design is fine, but the materials would look at home inside a $12,000 Chevy Aveo. The problem is that a WRX starts at double the price, and the STi jumps off at $10,000 more than that. The plastics are hard and shiny in some places. At least the steering wheel is wrapped in leather and has a nice thick grip.
Both cars have the same seats, with the WRX getting fabric upholstery and STi leather and alcantera. Aside from the upholstery, from the drivers seat there isn't much to choose between the two models. There are some extra controls on the center console of the STi aft of the gear lever. These knobs provide some degree of driver control over the center differential and electronic throttle, which Alex will go into full detail about in his review, and we'll gloss over here.
The Driver Controlled Center Differential system lets the driver switch between modes that keep the center differential open or tightened up. The open mode allows for freer steering, especially around tight corners, while the Auto (+) setting is best reserved for slippery surfaces. The SI-DRIVE system lets the driver modify the responsiveness of the throttle to accelerator pedal inputs. The Sport Sharp mode provides more instantaneous throttle response while the Intelligent mode shaves off the edges and gives a milder, smoother response.
The SI-DRIVE modifies the throttle response, but unfortunately does little for the problem of turbo lag. The STi, however, produces significantly more peak power than the WRX and can beat the lesser model handily in full bore acceleration. The STi will run 0-60 in 4.8-4.9 seconds ,while the WRX takes about a second longer. In day to day driving, however, that extra power isn't really very useful. Extracting it requires revving the engine in a manner likely to attract unwanted attention from ticket writers. Below about 4,000 rpm, the STi engine feels decidedly weak than its overt exterior suggests. Once the needles on the boost gauge and tach start to get active, so does the engine and the STi leaps forward.
By comparison, the power in the WRX comes on almost instantly. As soon as you tickle the right pedal and ease out the clutch, the WRX leaps off the line. Driving around in any gear, as long as you're not lugging the engine, the WRX just feels much stronger and more responsive. There's 226 lb-ft of torque at 2,800 rpm in the WRX, while the STi engine reaches its maximum of 290 lb-ft at a much higher 4,000rpm. Of course, at some point the STi will run away and hide from the WRX, just not in regular driving. That's the price you pay for the lower 8.2:1 compression ratio and higher 14.7 psi (vs 11.9 psi in the WRX) maximum boost pressure.
Both cars have a similar engine note that's more or less unique in the automotive landscape. The mechanical sound of a Subaru boxer engine is unlike anything else except perhaps a Porsche engine with a comparable layout. Neither of these cars is quiet at any time when they are on the move. At highway speeds, there is plenty of wind and mechanical noise and neither model could be described as refined.
Driving around in both cars, another readily apparent difference is the suspension compliance. Neither car could be described as soft, but the STi definitely veers toward harshness. Michigan roads will test any car's ability to keep its rubber on the pavement, a skill that is necessary in order to provide cornering grip. The WRX ride is firm but doesn't beat you up, while the STi seems much better suited to the pavement you might find in places that don't experience 50 degree temperature cycles from one day to the next. One huge advantage of either Impreza is the rear-biased all-wheel-drive system, which, unlike a Dodge Caliber SRT-4, never has any issues with torque steer under hard acceleration.

When the weather turns nasty, like it did when we had each of these cars, the rally heritage of the all-wheel-drive system shows its true colors. Turning into a snowy corner and goosing the throttle swivels the back end of the car around nicely past the desired direction before the drive torque balance shifts toward the front axle to pull you through the corner. It all works smoothly and seamlessly and is great fun.
So is the STi worth $10,000 than a regular WRX? As always, it depends. If you can't live with the hatchback styling and want to choose the sedan, you are limited to the WRX. If you can live with the looks of the hatch, the decision gets a little more complicated. If you reside somewhere with smooth pavement (that is not Michigan) or you regularly spend weekends at the track and don't mind the high strung nature of the high-boost turbo engine, the STi will fill the bill. On the other hand, if you're in the market for a daily driver, the WRX is actually a lot more fun to drive at speeds won't cost you your driving privileges. It leaps off the line and the torque band feels broad and useful instead of peaky like the STi. Both cars have good grip and their advanced all-wheel-drive systems allow them to be utilized under all kinds of weather conditions. From the driver's seat, each car is rowdy and raucous, but the WRX gets my vote as a daily rally machine.