Ford Unveils Ford Fiesta for North America at Los Angeles Auto Show; 1.6L I4 with Ti-VCT Delivers Estimated 40 mpg Highway
|Fiesta four-door sedan. Click to enlarge.|
Ford unveiled the North American 2011 Ford Fiesta at the Los Angeles Auto Show. Fiesta—available in four- and five-door bodystyles—will offer North American buyers a new choice of 15 class-exclusive technologies and projected highway fuel economy of 40 mpg, besting the Honda Fit, Nissan Versa and Toyota Yaris and Corolla.
The Ford Fiesta’s 1.6-liter DOHC I-4 engine delivers an estimated 119 hp (89 kW) @ 6,000 rpm and 109 lb-ft (148 N·m) of torque @ 4,250 rpm. Fiesta features Twin Independent Variable Camshaft Timing (Ti-VCT) (earlier post) which allows the engine to be downsized for fuel economy while continuously optimizing camshaft phasing for throttle response, performance and flexibility.
Ti-VCT gives precise, variable control of valve overlap; such valve overlap management is critical to eliminating intake and exhaust flow compromises.
This technology also optimizes phasing on both intake and exhaust camshafts by spinning them ever so slightly to advance or retard valve timing, resulting in improved throttle response at initial throttle tip-in, reduced emissions at part throttle and enhanced efficiency at higher rpm. The outcome is more power, responsiveness and fuel efficiency from less overall cylinder displacement.
During development of this global engine measures were taken to keep overall powertrain weight as low as possible.
The block, cylinder head and oil pan—traditionally the heaviest engine components—are aluminum castings. To increase rigidity, these elements are ribbed for additional strength and durability. Pistons are cast aluminum, as well, with the light weight helping to reduce reciprocating mass and adding to fuel efficiency.
Composite material is employed to keep intake manifold weight to an absolute minimum while allowing for induction routing to increase thermal efficiency and improve low-end torque characteristics.
Another Fiesta powertrain innovation is the new Front End Accessory Drive (FEAD) belt with stretchy dynamics, to improve the engine’s thermal properties. The elasticity in this new drive belt eliminates the need for a tensioning device. This decreases under-hood complexity and weight, helps increase fuel economy, and eases belt replacement at specified mileage intervals.
Fiesta is classified as US Tier 2 Bin 4 and California SULEV for tailpipe emissions.
|“Our fuel economy leader is now a PowerShift automatic. Traditionally, a small car driver needed a stick shift and a clutch pedal to enjoy the greatest fuel efficiency.”|
|—Barb Samardzich, vice president of Ford global powertrain engineering|
Transmission. Fiesta launches with an all-new, North American industry-exclusive PowerShift six-speed automatic transmission combining the responsive performance of a manual shift with the convenience of a traditional automatic.
PowerShift is a dual dry clutch transmission, operating with sealed internal lubrication, reducing friction and adding to Fiesta’s fuel economy. The lack of pumps and hoses reduces complexity, saves weight and contributes to fuel efficiency.
Fiesta’s PowerShift transmission gives better fuel efficiency than a traditional torque convertor automatic or manual shift transmission.
Twin internal clutches keep the PowerShift in constant mesh, continuously optimizing for maximum responsiveness and fuel efficiency, depending on engine speed, vehicle speed and input from the driver’s foot on the accelerator pedal.
Fiesta offers customers a standard five-speed manual transaxle with the ideal combination of gearing to provide swift acceleration from rest, responsive power at mid-range speeds and relaxed highway cruising in the overdrive fifth gear. Hydraulic actuation makes for smooth engagement with an easy-to-modulate clutch pedal, reduces the potential for slip and helps fuel economy.
Fiesta also features Electric Power Assist Steering (EPAS), which decreases complexity, saves weight and improves fuel economy by reducing parasitic drag on the engine in comparison to traditional hydraulic power-assisted steering. EPAS is speed-sensitive, providing optimized assist based on vehicle speed, steering wheel angle, cornering forces and acceleration or deceleration.
For the Fiesta application, EPAS is tuned to provide an engaging driver experience.
EPAS enables Pull-Drift Compensation to help Fiesta track true. This software-based technology detects road conditions—such as a crowned road surface or blustery crosswinds—and adjusts the EPAS system to help the driver compensate for the pulling and drifting these conditions can cause. Pull-Drift Compensation is designed to be imperceptible to the Fiesta driver.
In addition, EPAS enables Active Nibble Cancellation. This technology senses for irregularity in wheel balance and the related steering wheel vibration —“shimmy”—it can cause. Like Pull-Drift Compensation, Active Nibble Cancellation is designed and integrated to be seamless and unnoticeable to the driver while sensing and compensating for rotational oscillations due to wheel balance issues or uneven brake rotor wear.
More than 50% of Fiesta’s welded body structure is made from high-strength steel, with ultra-strong boron steel used in several critical areas. This rigid body shell contributes to Fiesta’s confident road-holding, best-in-class occupant safety and quiet composure.
For North America, the global Fiesta was tweaked, not re-designed or re-developed. We built on the success of the European Fiesta and are really proud of how little has changed.
—Steve Pintar, chief engineer
Fiesta is the next milestone under the ONE Ford plan to design and develop vehicles that meet the differing needs, wants and expectations of customers around the world. The car is Europe’s No. 2-selling car and Ford of Europe’s top-selling vehicle, helping increase Ford’s share in Europe’s main 19 markets. More than 500,000 Fiestas have been sold since the car was launched last autumn.