|Mustang 2.3L EcoBoost. Click to enlarge.|
Ford revealed its new 2015 version of the Mustang (with great fanfare simultaneously in six cities on four continents and CEO Alan Mulally on ABC’s Good Morning America) with a choice of three powertrains: a upgraded 5.0L V8, a 3.7-liter V6 and an all-new 2.3-liter EcoBoost engine developed specifically for Mustang.
Among the features of the new EcoBoost engine are an optimized intake manifold and turbocharger housing to provide better breathing and higher output. The new 2.3L EcoBoost offers a projected 305-plus hp (227 kW) and 300-plus lb-ft (407 N·m) of torque. (The upgraded V8, at more than twice the displacement, offers around 420 hp and 390 lb-ft.)
This EcoBoost engine delivers the healthy output that Mustang drivers expect regardless of the speed. This EcoBoost engine might be small in displacement, but it delivers where a Mustang driver expects it with a broad, flat torque curve and great driveability under any conditions.—Scott Makowksi, EcoBoost powertrain engineering manager
The newest member of Ford’s global family of EcoBoost engines, the 2.3-liter continues to take advantage of technologies including direct fuel injection, twin independent variable camshaft timing and turbocharging to produce bigger-engine power and torque with improved fuel efficiency.
|New Ford Mustang. Click to enlarge.|
This is the first Ford engine to utilize a low-inertia twin-scroll turbocharger that provides quicker boost response while enabling lower emissions and improved efficiency. The cylinder head features an integrated exhaust manifold that separates the inner and outer pairs of cylinders into each inlet passage to the turbo.
Keeping the exhaust pulses separated from the next cylinder in the firing order eliminates mixing losses and maximizes pulse energy to the turbine wheel. The result is quicker torque delivery when the driver needs it for passing maneuvers and similar performance to a twin-turbocharger configuration.
The separated exhaust ports also enable the exhaust valves to stay open longer for reduced pumping losses that improve specific fuel consumption by about 1 percent, Ford said.
Enhancements to the Mustang EcoBoost engine to withstand the added stresses of its higher power and torque delivery include:
- Forged-steel crankshaft
- Piston-cooling jets
- Steel piston ring carriers
- Premium bearing materials
- Upgraded valve seat materials
- Forged-steel connecting rods
- High-pressure die-cast aluminum cylinder block with ladder-frame bearing caps
- Deep-sump, die-cast aluminum oil pan
The V8. Ford’s 5.0-liter V8 for Mustang features a number of upgrades that enable it to breathe better, especially at higher engine speeds. Many of these changes are derived from the lessons learned in developing the special edition 2013 Mustang Boss 302.
|V8. Click to enlarge.|
Getting air into the cylinders and exhaust out—the focus of development of the new V8—is the key to generating more power and torque from any engine, Ford noted. The Mustang V8 features:
- Larger intake valves
- Larger exhaust valves
- Revised intake camshafts
- Revised exhaust camshafts
- Stiffer valve springs to ensure that the valves close completely at high rpm
- New cylinder-head casting with revised ports that provide a straighter path to the valves for less-restrictive intake and exhaust flow; combustion chamber modifications accommodate larger valves
- Sinter-forged connecting rods that are lighter and more durable for high-rpm operation
- Redesigned piston tops with deeper cutouts clear the new larger valves
- Rebalanced forged crankshaft to support higher-rpm operation
These upgrades are projected to generate more than 420 hp (313 kW) and 390 lb-ft (529 N·m) of torque.
A new intake manifold includes charge motion control valves to partially close off port flow at lower engine speeds. This increases the air charge tumble and swirl for improved air-fuel mixing. This results in better fuel economy, idle stability and lower emissions.
The variable camshaft timing on the intake side now has a greater range of adjustment available thanks to mid-lock phasers. This enables better optimized control of the valve timing over a broader range of engine speeds and loads for improved fuel economy and emissions
Transmissions. Mustang offers a choice of a fully manual gearbox or an updated automatic transmission. The Getrag manual has a new shift linkage design for shorter throws and improved precision. The shift lever is now positioned closer to the driver and away from the cup-holders so the driver has a clear path for shifting.
The automatic also features a redesigned case with cast-in ribs that help make it stiffer and reduce the weight. Internally clutches have been optimized and operating temperature has been increased to reduce friction. The output shaft is now supported by a ball-bearing that enables a top speed of 155 mph (249 km/h) for Mustang GT.