2011 Mustang GT's 5.0L Engine - Return Of The 5-Liter Mustang

Simply stated, the "5.0" engine encompasses great meaning to many Mustang fans, both old and young. When the Fox-body Mustang hit the streets in 1979, the V-8 powerplant featured 8.4:1 compressio and a two-barrel carburetor, and produced a wild 140 hp. By 1987 the 5.0 H.O. was fuel injected and making 225 hp. It was a player in the performance war, going head-to-head with GM and Chrysler's best.

Real performance was on the comeback and the 5.0L Mustang offered the best bang for the buck. It was cheaper than either F-body, the Corvette, or the powerful GN, and in the right hands could do amazing things. Early 5.0 pioneers like Steve Collison, Tony DeFeo, Neil van Oppre, Lee Rutter, Nitrous Pete Misinsky, Brian Wolfe, and Stormin' Norman (to name a few) pushed 5.0L Mustangs past what anyone thought was possible. They ran 12s, 11s, and then 10s with basic bolt-ons and tuning-and they did so at the time when 11s and 10s were reserved for racecars or big-block muscle.

Magazines like Cars Illustrated and then MM&FF dedicated page after page to 5.0L performance, focusing on new technology, fresh parts, and real-world dragstrip testing. We reported feverishly on those LX and GT models that proved to be fast, reliable, (save for the T-5) and ultimately, limitless in performance.

Sadly, the 5.0 era came to an end in 1996 when Ford switched to the modular Two-Valve 4.6L engine. Due to lacking performance, some appeal slipped away, but thankfully Ford eventually turned the 4.6L into a winner, making over 300 hp. The last variant will go to bed in 315hp form in the 2010 GT.

Nevertheless, Mustang enthusiasts crave more, and for 2011 Ford will deliver the goods with an all-new 5.0L V-8. More than just a beefed 4.6L modular, the "new" 412hp 5.0 features a fresh design with a slew of technological advancements that will produce an efficient 82 hp per liter and at least 25 mpg-and it makes as much torque as a Terminator! Important features include 11.0:1 compression, variable cams that help produce a broad torque curve, a new composite intake, 80mm throttle body, and tubular headers.

Though all of the components of any engine are parallel and work in harmony, the cylinder heads were the first major design project. Todd Brewer and John Reigger lead the way. The team agreed that the heads had to be a Four-Valve, DOHC design.

Once a prototype of the new compact Four-Valve head was built, the team tried the new cylinder heads on surrogate engines using existing FRPP camshafts to test for power output and torque curves. The end result is said to outflow GT500 heads by 4 percent. After studying what camshaft profile worked best for the new head design, a set of prototype cams was computer-designed by Kevin Shinners and John Carter, and cut for testing. "For the first time ever, we only ground one set of cams," said Adam Christian, ICE engineer (Intake, Combustion, and Exhaust). It usually takes dozens of prototype cams to find the right combination.

The all-aluminum block, though it features 100mm bore spacing, bears little resemblance to its predecessor. Cast-iron four-bolt main-bearing caps with side bolts hold the forged steel crankshaft steady, even at 7,000 rpm. Large oil passages are built into the block to allow the oil to flow back to the pan faster and with less restriction. The coolant crossover is now built into the block, eliminating coolant passages in the intake manifold. This is good for performance because the hot coolant doesn't heat up the incoming air charge. The rods are a familiar forged powder metal with a floating pin, and the pistons are hypereutectic aluminum, but there are oil squirters to cool the pistons and help resist detonation. Compression ratio is a stout 11:1.

Though some would argue an aluminum intake manifold is preferable, the team opted for a composite plastic design. "The plastic is smoother, more consistent, and heat transfer is lower," remarked Adam Christian. Not only is the plastic intake lighter and less expensive to manufacture, it makes 1 to 2 percent more power than an aluminum version.

The finished aluminum cylinder heads house two 37mm (1.46-inch) intake valves and two 31mm (1.22-inch) exhaust valves, compact roller fingers, and vertical 193cc intake ports. Port and Combustion Chamber Engineer Jim Froling perfected the chamber and runner design, complete with round exhaust ports, absent from the Three-Valve.

A new firing order forced the team to create a new design for the exhaust manifold. The team wanted to create a tubular header, but power loss, due to paired cylinders on each bank, disallowed use of a tri-Y design like conventional performance headers. With only two weeks left before tubular headers were scratched for cast manifolds, Christian thought of the idea of using a twin-T design. "I gave him a bunch of bent tubing, and he built the prototypes over the weekend in his garage," said Harrison. Though they look inefficient, we project long-tubes will only yield about 15 hp over these stock units.

Aesthetically, the photos speak for themselves. The partial engine cover allows the intake to peek through but covers things like the wiring harness and injectors.

To meet the performance and economic needs of the new engine, new automatic and manual transmissions will be standard on the 2011 Mustang GT. The 6R80 six-speed automatic has a wider ratio span, can handle a higher torque output, and allows for 3-5 percent better fuel economy over the 5R55. The MT82 manual transmission features low shift effort, a new fully synthetic oil, and is more durable and efficient than the current TH3650.

The last, and probably most simple, standard feature on the '11 is the new "5.0" badge. Found on the engine cover and fenders, it takes a new spin on the original. The red decimal looks almost identical, only slightly larger, and the font of the numbers is reminiscent, yet modern. It's big enough for the larger S197, but not gaudy.

Gone is the Three-Valve modular; in its place we have an attractive and balanced specimen that far exceeds our expectations. Overall weight is within a few pounds of the Three-Valve, thanks to a smaller and lighter valvetrain, but power output has been increased by roughly 100 hp. We smell 12-second quarter-mile e.t.s right out of the box.

Once again, Ford Motor Company nailed the exercise, and now all that's left for us is to drive one.