2011 Ford Mustang GT

The Return of the 5.0 -- and a New Boss 302R Racecar

December 28, 2009 / By Frank Markus Click Here for Complete Article

First things first. With a bore of 92.2mm and a stroke of 92.7mm, the high-tech DOHC 32-valve engine under the hood of the 2011 Ford Mustang GT making its debut at the 2010 Detroit show displaces 4951cc. That figure legitimately rounds to 5.0 liters, unlike the 4942cc displacement of its pushrod predecessor. That overgenerous rounding drove some of us persnickety engineering types crazy for all those years, so right off the bat we're inclined more favorably toward this new V-8. Indeed there is a lot to like about this high-tech engine, starting with its output figures: 412 horsepower and 390 pound-feet of torque (on recommended but not required premium fuel, slightly less on regular no-lead).

Designed according to best-practices established in the design of the 3.5 and 3.7-liter V-6's as well as the 6.2-liter V-8, the Mustang GT's new 5.0 boasts cam-torque actuated variable valve-timing on the intake and exhaust cams plus a long-runner single-scroll intake manifold and tubular stainless headers to optimize breathing. Moving the alternator out of the valley opened up space for the 80mm throttle body to breathe directly into the larger intake manifold. To cope with the engine's 11:1 compression and high combustion stresses, the crank is forged steel and fully counterweighted, using forged powdered-metal connecting rods, floating wrist pins, and hypereutectic pistons cooled by oil jets. The bulkheads are also 2mm wider and the six main bearing bolts are larger than those in the 4.6. This is reportedly as large a displacement as this architecture can handle with the 1.2mm cylinder liners and the current deck height (a slightly larger bore could be accommodated by switching to a spray-lined cylinder design).

The unique new cylinder heads will not bolt up to earlier 4.6's. The exhaust cam has been moved down and outboard, so the intake cam could also move outboard a bit for a more vertical intake valve geometry. Extremely light valves and compact roller finger followers permit the engine to rev to the speeds of 7000 rpm. To cope with the extreme g-loading experienced on a track and enable a 10,000-mile oil-change interval, the oil capacity has been increased to eight quarts. Extensive baffling and redesigned oil return galleys ensure that the cylinder head oil drains and the oil pump pickup is supplied even at sustained 1g lateral loads.

The 2011 Ford Mustang GT marks the return of the 5.0 V-8 to the Mustang's engine bay, rated at 412 hp at 6500 rpm and 390 lb-ft of torque.