- The Washington Times - Friday, August 8, 2008

Dodge addressed the performance demands of today’s fuel-crunched, full-size-pickup buyer in a recent announcement at its Chelsea, Mich., proving grounds.

Bob Lee, vice president of Chrysler’s powertrain product engineering team, said the 5.7-liter Hemi V-8 powering the new-design 2009 Dodge Ram 1500 provides “best-in-class” output, improved fuel economy and better idle quality.

The new-generation Ram’s 5.7-liter with Multiple Displacement System eclipses its 2008 Hemi counterpart with 13 percent more horsepower, an 8 percent torque boost and a 4 percent fuel economy increase.

An output of 390 horsepower and 407 lb.-ft. of torque trumps the 2008 version’s 345 horses and 375 lb.-ft. of torque. Dodge reports this is enough punch to launch an R/T regular-cab 2WD model from 0-60 mph in less than 6 seconds.

With its 26-gallon tank filled with recommended 89-octane or acceptable 87-octane gasoline, the 2009 model gets up to an estimated 20 miles per gallon on the highway (no official fuel economy figures are available).

This improved power and fuel economy, Lee said, can be attributed to upgrades using several technologies.

Output is optimized with Variable Valve Timing, which strategically advances or retards the timing of the intake or exhaust valves.

Teaming with VVT is a new active intake manifold with a short- and long-runner arrangement that helps boost low-end torque and horsepower. Long runners contribute to improved low-end torque and short runners increase power at high rpm.

Operating range of the MDS, which automatically switches back and forth from eight- to four-cylinder mode, has been expanded. A torque increase in four-cylinder mode allows use of the mode more than in the past.

Under normal conditions, and even when encountering mild hills, the 2WD Ram runs in four-cylinder mode - generally from 30 to 50 mph. Rolling on flat, smooth pavement, it could run on four cylinders up to 60 mph.

Also on this list of performance boosters are improved cylinder-head-port-flow efficiency, and reduced-restriction exhaust and induction systems. Complementing the Ram’s performance and fuel economy is improved aerodynamics.

“Aerodynamics is huge,” Lee said. “That’s what makes highway performance better. Over about 40 mph, aerodynamics starts to get good in this truck.”

The truck was designed with aerodynamics as a priority, said Ralph Gilles, Chrysler Group director of product design. Drag is lessened up front with a hood bulge and a “little kick up” on the hood, right before the wipers. The wipers are much more submerged and protected from the wind.

Door cuts are a side-view style vs. the 2008’s aircraft design. This helps quell wind noise and keeps the sills out of the air path. Sills also are lowered - covering the frame rails - to prevent air from getting under the vehicle. The Ram also cheats the wind with better-sealed windows and more sculpted exterior mirrors with smaller necks.

While aerodynamics increases performance at higher speeds, weight reduction improves the Ram’s performance in city driving. The Ram sheds about 80 pounds for 2009, said Dodge Ram Chief Engineer Mike Cairns.

Weight-saving measures include: an aluminum hood; thinner-gauge, higher-strength steel used in the frame and body; and significant front- and rear-suspension re-engineering.

Up front, the suspension features aluminum knuckles and control arms. A five-link coil rear suspension, replacing the venerable leaf springs, decreases weight by 40 pounds.

With the exception of extra costs, the five-link suspension (it still has a solid axle) comes with a list of benefits and no sacrifices in payload hauling and towing. Using a track bar that has double the stiffness of leaf springs, ride quality and handling are greatly enhanced. It also adds to trailer-towing stability.

Coming in 2010 is the Ram 1500 Hybrid, which Dodge reports delivers a 40 percent fuel economy improvement in the city and 25 percent overall. This dual-mode hybrid system pairs the 5.7-liter Hemi V-8 with electric motors.

The hybrid powertrain can propel the truck during slow starts on electric-only power up to 25 mph. High-torque electric motors give a power assist to help keep the engine on its “MDS edge,” Lee said, to extend four-cylinder-mode operation.

Hybrid and MDS efficiency are coming to the rescue in a timely manner, increasing the odds of a solid future for old-style Hemi V-8 muscle.



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