Road Test: Comparison Test

Comparison Test: 2008 Subaru Impreza WRX vs. 2007 Mazdaspeed 3
Two Affordable Turbocharged Wagons Face Off


By John Pearley Huffman, Contributor
Date posted: 08-05-2007



Sport compacts have it hard. Cars like the 2008 Subaru Impreza WRX and the 2007 Mazdaspeed 3 — along with competitors like the Honda Civic Si, Mini Cooper S and Volkswagen GTI — are expected to do mutually contradictory things with something approaching perfection. They're supposed to be quick but economical; athletic but comfortable; sporty but practical. Oh yeah, and they can't cost a lot.

Go ahead and dream the impossible dream.

In last year's six-car sport compact comparison test it was the then-new 2007 Mazdaspeed 3 that did the best job of pulling off those tricks. And just behind it in 2nd place was the 2006 Subaru WRX TR. Now, with the 2007 model year dribbling to an end, Subaru has introduced a new 2008 WRX that's both lighter and roomier.

But is it enough to knock the Mazdaspeed 3 off its precarious perch?

Subie Do, Mazda Do, Too
By stretching the Impreza WRX's wheelbase 3.7 inches to 103.1 inches, Subaru has produced a significantly roomier cockpit for passengers. Meanwhile, the new five-door body style (a four-door sedan is also offered) keeps the overall size tidy with minimal overhangs and total length of just 173.8 inches — 2 inches shorter than the 2006 WRX TR four-door sedan. Width remains unchanged at 68.5 inches while overall height has risen from 56.7 to 58.1 inches.

At 3,167 pounds, the all-wheel-drive WRX wagon is only 45 pounds heavier than the 2006 WRX TR and 9 pounds lighter than the five-door Mazdaspeed 3, despite the fact that only the Mazda's front wheels are driven.

This is partially due to the Mazda's slightly larger size. Its wheelbase is 0.8 inch longer than the Subaru's and its total length is 3 inches greater. It's also an inch wider and half an inch taller.

So they're sized about the same inside and out, but under their skins these turbocharged wagons couldn't be more different.

Powerful Arguments
Subaru and Porsche are the only carmakers that still believe in the benefits of the flat engine. The new WRX's turbocharged and intercooled 2.5-liter DOHC 16-valve horizontally opposed four is an updated version of the same engine that's been powering Subarus since Wisconsin was admitted to the union.

Now rated at 224 horsepower at 5,200 rpm (400 rpm earlier than in '07), Subaru has given up a bit of peak power to improve low-end torque, and 226 pound-feet at a mere 2,800 rpm (down 800 rpm from before) is impressive. Bolted to the engine is a five-speed manual transaxle that feeds the Subie's ubiquitous all-wheel-drive system.

In contrast, the Mazdaspeed 3's power plant appears relatively conventional: a turbocharged and intercooled 2.3-liter DOHC 16-valve inline-4. But this is Mazda's Direct Injection Spark Ignition (DISI) engine — the same advanced technology power plant Mazda puts in the larger Mazdaspeed 6 sedan and CX-7 crossover.

Using a direct-injection fuel system, the DISI is rated at 263 hp at 5,500 rpm and 280 lb-ft of peak torque at a measly 3,000 rpm. It's also particularly smooth thanks to a pair of counterrotating balance shafts that knock out most vibrations. It's attached to Mazda's compact "three-shaft" six-speed manual transaxle that supplies power to the front wheels.

Door Handle to Door Handle
The generous torque band and distinctive sound (sort of like a VW Beetle operating underwater — which, in a sense, it is) of the Subaru's flat four are as appealing as ever, but it just doesn't have the same thrust and flexibility of the Mazda motor.

Although the Subaru's 5.9-second 0-60 time is two ticks better than the Mazda's 6.1-second clocking, it's all due to its traction advantage at launch. By the end of the quarter-mile, the two cars are dead even at 14.5 seconds and the Mazdaspeed 3 is going 98.7 mph compared to the WRX at 94.4 mph. Considering the difference in power ratings, none of this is surprising.

The surprise was that this Mazdaspeed 3 was slower than the preproduction Mazdaspeed 3 in last year's comparison test. That car made it to 60 in just 5.9 seconds and traipsed through the quarter-mile in 14.2 seconds at 100.1 mph.

Because this production Mazdaspeed 3 was absolutely brand-new with less than 500 miles on its odometer, it may just be that its engine would loosen up with some mileage and it would get quicker. Or it could be a natural variation because the cars were tested on different surfaces. Or maybe the engineers were just extra, um, attentive to the preproduction car. Feel free to speculate.

Either way, there's no denying the Mazdaspeed 3's torque steer on launch, but in most every other respect, the combination of the DISI's flexible power band and the sure-shifting six-speed gearbox is significantly better — and ultimately quicker — than the Subaru.

Suspension of Disbelief
Sometime during the development process, Subaru decided to skip roll stiffness as part of the WRX's suspension tuning equation. The car has good reflexes, but go into a corner hard enough and by the apex you're half expecting to scrape a sideview mirror off on the tarmac. We also miss the tossability of the old WRX, which has been replaced with understeer.

A new double-wishbone independent rear suspension replaces the struts used on the previous WRX, but the lack of roll stiffness doesn't seem to be isolated to the tail. Instead this seems to be a choice by the engineers to maximize ride comfort at the expense of cornering prowess. As it is, the WRX's 0.81g skid pad and 67.7-mph blast through the slalom are solid, but not up to the Mazdaspeed 3's better 0.86g skid pad twirl and outstanding 69.3-mph slalom performance.

Noticeably stiffer than the WRX without being uncomfortable, the Mazda's turn-in and steering response are among the very best around and the car remains flat even in grossly off-camber corners. This is an excellent-handling machine, but like the Subaru it's not really possible to rotate the car around corners. The levels of adhesion are high enough, however, that the car is absolutely blazing before it heads into understeer.

As in the previous WRX, the new WRX's steering is quick, precise and nicely weighted. The steering is heavier than the Mazda's, but it provides great feedback. Both cars also have effective four-wheel disc brakes and unobtrusive antilock systems. The Mazda took 113 feet to stop from 60 mph while the Subaru needed 121, but both cars would be better with brake pedals that had more progressive actions and more feel.

On a mountain road, the Mazda is fun to toss in a way few other cars priced under $30,000 are. And it's satisfying to drive even slowly.

Everyday Cars for Every Day
Ford's C1 platform underpins the Mazda 3 and Mazdaspeed 3 (as well as Volvo's C30 and S40) and it's the most substantial-feeling compact-car chassis out there. In the Mazdaspeed 3 the ride is stiffer than in other C1s, but it's always poised, even when chucking itself from pothole to road divot to gutter crack. And it's relatively quiet, doing a good job of isolating out most road noise despite the car's relatively large 215/45ZR18 Bridgestone Potenza RE050A summer-spec performance tires.

The WRX, on the other hand, transmits more road noise through its structure, even though less aggressive 205/50R17 Bridgestone Potenza RE92A tires are fitted. The Subaru feels tight and well built, just not as impregnable as the Mazda.

Its lower cowl height, an advantage of that flat engine, gives the WRX better overall visibility than the Mazda, but Subaru didn't press that advantage with the WRX's interior design. Like its exterior, it's somewhat drab and uninspired.

The front seats, for instance, have nicely shaped backs but the seat bottoms are flat and everything is upholstered in two tones: drab gray and drabber black. There's plenty of room for stuff in this logically laid out interior, and the oversize, easily read gauges glow a brilliant red, but no one in there is going to be overjoyed by what they see. At least they kept the tach in the center of the instrument panel, which should keep the faithful satisfied.

Mazda hasn't been shy about decorating the Mazdaspeed 3's interior. There are aluminum covers for the pedals, red accent stitching on the steering wheel and upholstery and the seats have been assertively bolstered for support. Turn on the Mazdaspeed 3's radio and red LEDs light up in sequential celebration of the system's activation. If the Mazdaspeed 3 interior's flamboyance is too much, then maybe the whole car is too flamboyant for you. But it looks like a sporty car's interior. And in practical terms, it's at least as usable for day-to-day tasks as the Subaru.

Price Matters
At just over $25,000, the Mazdaspeed 3 isn't cheap. But the Subaru WRX came in at an as-tested $27,595. Of course the WRX has the advantage of all-wheel drive and if you live in Colorado, New Hampshire or Vermont that can make all the difference come wintertime. Still, if performance-bang-for-your-hard-earned-buck is the bottom line, you'll be better off moving to a warmer climate and buying a Mazdaspeed 3.

It's hard not to be somewhat disappointed by the Impreza WRX. It's a good car, but it's wrapped in lackluster sheet metal and doesn't have the edge it needs to be a consistently entertaining driving companion.
Last year the Mazdaspeed 3 rose to be crowned the king of the sport compacts. Its spot on the throne is safe for now.