Corolla comes of age: Toyota's 2003 Corolla brings new levels of sophistication to the small car segment - New Product: 2003 Toyota Corolla

Automotive Industries, Jan, 2002 by Gerry Kobe

Perspective is everything.

Consider the hoopla that was made about the 35th anniversary of the Ford Mustang. Members of Mustang clubs filled the streets, vintage cars went on display and Ford aficionados bragged about the car's admittedly small but extremely loyal share of the U.S. market.

Thirty-five years ago, another vehicle launched. There will be no celebration of its anniversary, but it is the all-time best-selling passenger car in the world at 28 million units. It is available in 142 countries worldwide and currently assembled in 14 of them. It has also been the best-selling car in Japan for the last 32 years. That car is the Toyota Corolla, now entering its ninth generation and unquestionably better than ever.

"The secret to Corolla's popularity is that it has changed along with people's needs," says Chief Engineer Takeshi Yoshida. "It is an important car to young people and if we can fill their needs, we can have a customer for life."

Indeed, Corolla has met the needs of its buyers over the past several decades. It was a cost leader in the frugal 1960s, a fuel sipper in the energy-conscious 1970s, a bastion of quality in the dark period of the 1980s and a value leader through the 1990s. The image for the 2003 car is substance and sophistication. So at 35, Corolla has grown up.

Like all things that mature, Corolla has gotten bigger. The wheelbase is increased more than five inches to 102.4 and overall length goes to 178.3--a four-inch stretch. Even the height of the car has gone up three inches, with a combined effect of boosting passenger volume by more than two cubic feet and cargo volume by just over a foot. Rear seat legroom is the single largest beneficiary of the stretch, adding more than two inches compared to the previous car.

But more compelling than the size story is the fact that Corolla has become a repository of sophisticated components, materials and systems.

It starts with the 1.8L engine, a carryover from the previous car but a technology showcase with its VVTi, a variable valve timing system that varies intake cam liming by up to 40 degrees. The engine also makes 130 hp compared to last year's 125, thanks to a larger throttle body and redesigned intake manifold with a large central plenum.

Toyota also fits an extremely compact starter on this year's engine. The Denso unit is wound with square cross section copper wire, which puts 33-percent more copper in the armature, improving magnetic efficiency by the same percentage. In addition, the engine wears an advanced catalytic converter with an ultra thin wall ceramic catalyst bed. The low mass construction lets it heat up more quickly, which helps on the EPA emissions cycle.

In terms of structure, Corolla's body shell uses a clever approach that incorporates the door side guard beams to maximize performance in a frontal offset crash.

"We use tubular door guard beams instead of a more conventional folded 'W' design," says Paul Williamsen, curriculum manager at the University of Toyota. "The tube construction gives us a load path for frontal impacts to go around the body shell rather than into it. The door beams are angled high up on the A-pillar and go to the base of the B-pillar to carry forces around the passenger cell."

To augment the crush of the body, Corolla gets third-generation supplemental restraints, which offer multistage deployment for both driver and passenger. The bags have two igniters, which can be triggered simultaneously for a fast, hard fill or staggered for a softer, longer fill. There is even a seat track sensor on the driver's side that makes the bag default to a soft fill to protect shorter passengers.

Corolla has also been upgraded in both standard and optional equipment. Even the base CE trim package offers 15-inch wheels, power mirrors, AM/FM/CD with four speakers, 60/40 split seat back, tilt wheel, tachometer, light package and outside temperature display. Moving up to an S or LE adds luxury items like air conditioning with rear ducting and pollen filtration, leather seats and steering wheel trim, wood trim on the IP and a premium stereo with six speakers.

Beneath the skin, Corolla sticks with a fairly conventional MacPherson-type front suspension and a tried-and-true twist beam in the rear. Driving feel gets a dramatic improvement by relocating the steering rack to the front subframe rather than the body shell. There is far less vibration transmitted through the wheel and steering has a more precise feel.

Corolla also upgrades the front struts by incorporating linear control valves that instantly change shock valving based on the force of the impact. Rear struts get rebound springs, an upgrade usually reserved for SUVs or luxury vehicles. This helps increase roll stiffness without the ride penalties associated with a stiffer sway bar or springs.

Braking is handled by a disc/drum combination with ABS an extra cost option. The ABS includes electronic proportioning that permits front-to-rear and side-to-side balancing.

The '03 Corolla was a 31-month program, according to Yoshida. And while that is slightly longer than some programs and about equal to the previous Corolla development time, it included provisions for spinning two other vehicles off the same platform: the Matrix (see sidebar) and Pontiac's upcoming Vibe.