From Acura press: For 2003, the two primary goals for the MDX are to boost its already formidable performance by increasing horsepower and further refine the MDX inside and out. The 2003 version of the MDX features many improvements that enhance its best-in-class status including a next generation engine that boosts horsepower from 240 to 260 and an all-new compact 5-speed automatic transmission. Engine refinements make the MDX the first SUV to meet rigorous ULEV-2 emissions standards and allow it to achieve an impressive estimated fuel economy rating of 17 mpg city/23 mpg highway using the EPA method.
Revised suspension and steering systems coupled with a 35 percent increase in dynamic torsional chassis rigidity enhance ride comfort while maintaining responsive handling. A new Vehicle Stability Assist (VSA) system works in concert with the MDX's VTM-4 four-wheel drive system and innovative drive-by-wire throttle system to provide enhanced vehicle control during acceleration, cornering and braking.
An advanced powertrain is essential to meet 2003 MDX's goals of providing V-8-like performance, class-leading low emissions, and excellent fuel economy. To that end, the MDX is powered by an advanced 3.5-liter, VTEC V-6, engine. Through a 40 percent reduction in exhaust resistance, key changes to the intake manifold, and other enhancements, horsepower and torque have both been increased for 2003. The MDX powerplant now produces 260 horsepower at 5750 rpm, a 20 horsepower gain compared to last year, and boosts torque output to 250 lb-ft of torque between 3500 and 5000 rpm, a 5 lb-ft gain over last year.
Acura's renowned Variable Valve Timing and Lift Electronic Control (VTEC') valvetrain, first used in the NSX supercar, adjusts the timing, duration, and lift of the intake valves according to engine speed. In conjunction with a two-stage intake manifold, VTEC yields muscular response at low- and medium-rpm, high peak-rpm performance, very low emissions, and best-in-class fuel efficiency.
The more powerful engine is coupled to an innovative drive-by-wire throttle system, which eliminates the need for a mechanical connection between the cockpit and engine, reduces overall weight by incorporating the cruise control function and helps to reduces shift shock by communicating with the transmission during up and down shifts.