Ford Edge: Powertrain

[Edge Guide]

2007 FORD EDGE ALL-NEW 265-HP V-6, 6-SPEED DELIVER IMPRESSIVE PERFORMANCE AND SUPERIOR FUEL ECONOMY

 

* All-new, refined 265-hp 3.5-liter V-6 with variable cam timing and electronic throttle control delivers engaging performance

* Class-exclusive 6-speed automatic provides smooth operation and good fuel economy (expected mid 20s in highway driving)

 

With an all-new powertrain combination, Ford Edge delivers impressive performance feel. This crossover has near-luxury levels of quietness and refinement and fuel economy numbers associated with smaller vehicles.

 

Edge performance begins with an all-new 265-horsepower 3.5-liter Duratec 35 V-6 engine mated to a smooth and efficient 6-speed automatic transmission.

 

“Performance and good fuel economy can go hand-in-hand if you develop the right technologies,” says Barb Samardzich, vice president, Powertrain Operations, Ford Motor Company. “That’s why Ford is committed to 6-speed automatic transmissions, electronic throttle, variable cam timing and other advanced powertrain technologies.”

 

Powerful New V-6 Engine Designed to Deliver

 

Featuring a number of technological innovations, the new Duratec 35 engine delivers 265 horsepower and 250 pound-feet of torque for acceleration performance. It’s expected to be at or near the top of the medium crossover segment while achieving fuel economy in the mid-20s on the highway.

 

The engine’s intelligent electronic throttle body uses an accelerator pedal sensor to read and interpret the driver’s intentions. This sets the engine to run at its peak efficiency for both performance and fuel economy.

 

For improved fuel economy and high-rpm refinement, the engine features a forged-steel fully counterweighted crank shaft with induction-hardened journals, fractured-split, powder metal-forged connecting rods and high-temperature alloy, cast-aluminum pistons with low-friction coating.

 

The engine’s intake was designed as a system, all the way from the throttle body to the intake valves, to create optimum flow for peak power and to broaden the torque curve.

 

Computer-aided engineering (CAE) analysis was used to fine-tune the dual plenum manifold to deliver the required airflow rates without the need for intake flaps or butterfly valves in the plenum. This not only results in a broader torque signature, but eliminates the “hiccup” associated with engines equipped with butterfly-valve intakes.

 

Intake Variable Cam Timing Improves Smoothness and Refinement

 

The valve train is controlled by dual camshafts and direct-acting mechanical buckets that are more compact and lighter weight than common roller finger followers. The smaller size improves packaging efficiencies and reduces idle vibration.

 

Intake variable cam timing (i-VCT) optimizes valve timing for a smooth idle and helps the engine produce a broad torque curve. The i-VCT system uses a hydraulically actuated spool valve to control the movement of the cam phaser and can rotate up to 40 degrees, shifting within less than half a second.

 

Efficient Combustion Plus a Hard-Working Catalyst Equals Ultra-Low Emissions

 

Careful attention to detail in both the combustion system and exhaust after-treatment has produced an exceptionally clean operating engine. The powertrain team focused on four significant enhancements that aid in delivering an ultra-clean and reliable engine:

 

* The high 10.3:1 compression ratio effectively lowers emissions while improving both power and fuel economy.

* Low heat-loss exhaust manifolds and close-coupled catalysts for fast light-off during cold-start help minimize cold-start emissions before the catalysts reach operating temperature.

* Optimized fuel injector targeting also helps in minimizing cold-start emissions.

* Centrally located spark plugs increase the engine’s thermal efficiency.

 

Edge is expected to be rated for ultra-low emission vehicle (ULEV) II tailpipe emissions in California and receive a U.S. Environmental Protection Agency rating of Tier II/Bin 5 tailpipe and low-emission vehicle (LEV) II evaporative emissions in other states.

 

All-new, Class-Exclusive 6-speed Delivers Smooth, Efficient Performance

 

Edge comes standard with an all-new, class-exclusive 6-speed transaxle that improves fuel efficiency up to 7 percent in highway driving over 4-speed transmissions while offering better performance and smoother, more precise shifts.

 

“Ford is taking a leadership position in 6-speed automatic transmissions,” says Samardzich. “With the introduction of the Ford Edge, we will have a dozen models with 6-speed automatics in our showrooms, and more on the way.”

 

The 6F uses a wide-ratio 6.04:1 gear span to deliver maximum performance and fuel economy. The low 4.48:1 first gear provides tremendous acceleration at launch while the tall, 0.74:1 overdrive sixth gear provides exceptional fuel economy. Short steps between intermediate gears enhance performance and feel by finding the right gear for the most efficient operating conditions.

 

6F Design Delivers Impressive NVH

 

The elimination of noise, vibration and harshness (NVH) was a high priority of the development team. Every area of the transmission was scrutinized to provide smooth, quiet operation.

 

Powertrain engineers focused on the design of the interface between the engine and transmission to nearly eliminate the bending that occurs under acceleration, resulting in smooth launches and shifts.

 

Extensive use of CAE modeling on the transmission case built a solid housing for the transmission components. Engineers used analysis to determine exactly where strengthening ribs and wall thickness were needed to minimize radiated noise and vibration.

 

The three simple planetary gearsets are designed for robustness and use low-pinion pitch line velocities to reduce noise.

 

All gears are cut using high-precision CNC cutting machines. The transfer and final drive gears are hard finished, providing a more precise fit, reducing gear whine.

 

Unlike many transmissions where the gears are “green finished” (shaped and then heat treated) these “big gears” are treated and then finish machined. After grinding, the gears are honed or polished to remove “ghost lines” – the microscopic undulations left in the surfaces of the teeth after shaping. This additional step results in a 50 percent improvement in tolerances and greatly reduces gear-to-gear noise.

 

Innovative Control Strategy Improves Shift Quality

 

A single intelligent control module shared by the Duratec 35 and 6F transmission has a learning function that collects data each time the transmission shifts, measures the response and improves shift quality by adjusting shift parameters.

 

To ensure the best possible shift quality, each 6F transmission is bench tested at Ford’s Van Dyke (Mich.) Transmission Plant. There, the transmission build quality is verified, detecting even minute variations in the manufacturing process. Unique software programmed into the powertrain control module individually trims and characterizes all solenoids and clutches to compensate for variances that normally would lead to changes in shift feel. This strategy produces smooth, precisely controlled shifts that improve durability and customer satisfaction.