Packaging

The 2004 Acura TL is 3.7 inches shorter, 2.5 inches wider and incrementally taller than the previous TL.

In determining the overall dimensions of the new TL, the BMW 530i and Lexus ES 300 were the primary benchmarks. Audi's A4, the Infiniti G35, and the Mercedes-Benz C320 and S60 were secondary targets.

Rigidity

• Increased use of high strength steel accounts for a strong unit body structure that is also light.
• A front shock tower brace, a more rigid front bulkhead, a roof stiffener that extends to the C-pillar, and a new parcel shelf box section also contribute to stiffness.
• Improved attachment of the front frame rails, roof and rear panel and parcel shelf and larger rear unit body gussets also contribute to overall stiffness.
• The average torsional rigidity is 24 percent greater than the '03 TL and even better than the BMW 3 Series.
• The new front bulkhead substantially improves front lateral bending rigidity by 30 percent over the previous TL.

High-Tensile Steel

High-tensile 440 and 590 steel was used for 48 percent of the body. Even though the forming process is similar to that used for standard steel, the chemical composition of high-tensile steel allows it to be stronger after forming. Parts can therefore be made thinner and lighter while maintaining strength.

Aerodynamics

Achieving the desired exterior styling required that most of the cooling air come from under the front of the car. Several different polypropylene panels enhance underbody aerodynamic performance. These lightweight and durable panels include a curved valance below the front fascia. Air attaches to its smooth radius at highway speeds and is directed into the radiator. The center section of the valance bends out of the way if the TL encounters a curb or other obstruction.

Other aerodynamic elements include refined A-pillar shape, front and rear deflectors, an engine undercover and a rear floor cover. These underbody improvements benefit fuel economy, reduce wind noise and improve high-speed stability. Internal testing reveals that the 2004 TL betters the BMW 530i, Mercedes-Benz C320, Lexus ES 300 and Volvo S60 in coefficient of drag.

Reduced Wheel Arch Gaps

Minimizing the visual gap between the edges of the tires and the wheel arches was an important design goal. To retain a wide wheel track with these narrow gaps, the TL has a special fender flange design that allows the tires to sweep up and inside without making contact during suspension movement.

Mass Reduction

Keeping the 2004 TL curb weight low was a matter of the highest priority for Acura. Despite a comprehensive array of new technologies and the added use of insulating materials to promote an even quieter and more luxurious cabin, strict control over component weight has kept the new TL to just 3,575 pounds, only 17 pounds more than the 2003 TL Type-S. And at 3,482 pounds, the 6-speed model actually weighs 76 pounds less.

This small weight differential between '03 and '04 models becomes all the more impressive considering these 2004 TL improvements and additions:

• Improved body rigidity
• Side curtain airbags
• Larger wheels and tires
• XM Satellite Radio
• HandsFreeLink hands-free telephone connectivity
• 2-way power lumbar driver's seat support
• Tilt and telescope steering wheel
• Wider moonroof

Source: Honda PR