Is The New 5-Liter Engine Ready For Boost – A Look At The Internals
While the 2011 Mustang GT is just starting to hit the dealer lots, a few owners have already started to test the limits of new 5.0-liter modular engine. While nitrous is the obvious weapon of choice for an easy 1 to 2 second gain in ET’s, the question is raised how will the engine respond to forced induction like superchargers or turbos.
Currently Ford Racing is evaluating an intercooled twin-screw supercharger on the 5.0-liter engine. The supercharger is being developed for the 2011 Shelby GT350 and as a Do It Yourself kit for any 2011 Mustang GT owner. According to a recent YouTube testing video, Ford Racing has left the stock internals untouched and are running a safe 4-5 pounds of boost with excellent results. The supercharged 5.0-liter test engine has been evaluated using a 100-hour engine dyno test as well as a 4-hour chassis dyno pull at various temperatures and altitudes.
While some debate the 5.0 liter’s 11.5:1 compression ratio being too high for boost, Ford’s new variable cam engine technology is a brand new chapter in Ford engine performances. While the engine uses a few carryover features from the 4.6 modular engine, Ford says the 5.0 Liter design is brand new and the variable valve technology on all four cams is what allows the high compression engine to work well in boosted applications
The 5.0 Liter aluminum engine block is stiffer than previous 2 and 3 valve Mustang GT modular engines. The exterior block features more ribbing and cross-hatching to improve rigidity, a feature that should come in handy when enthusiasts start to add power parts like turbos or superchargers.
Photo Credit: Ford
The bore spacing is 100 mm and features eight 92.2 mm (3.629 inches) bores with 92.7 mm (3.649) stroke to equal 302 cubic inches – a historic number in Mustang history. As with past aluminum modular blocks, the engine features pressed in iron cylinder liners with a new thinner design to achieve the optimum bore size.
The crankcase of a production 5.0-liter block features thick fully machined main webs, oval PCV ventilation ducts and piston cooling jet mounts. The cooling jets are direct result from Ford’s race engine programs and are fed oil directly from the main oil galley. The piston cooling jets bolt to the underside of the block galley and aid in cold engine start-up and prevent detonation. The valley is also optimized for windage and oil drain back under high RPM and sloshing conditions.
The 5.0-liter engine block uses 6 bolt nodular iron main caps with larger bolts. Each cap is bolted to the block with four down bolts and two cross bolts. With such a tight bottom end, crank walk will be the least of your problems with this engine
5.0-Liter Mustang cranks are manufactured by Kellogg Crankshafts, and are fully counterweighted steel forgings. The counter weighting allows the crank to rev to 7,000 rpms with ease. The leading edge of the crankshaft journal-oiling hole is machined to improve oiling at high RPMs.
The connecting rods are forged from powdered metal and designed for reduced weight. The small end features a bronze bushing and full floating pin. With the 5.0 Liters center-to-center length the same as a 4.6-liter engine, we imagine the Manley H-beam type connecting rods found in the 2003-2004 Terminator Cobra would be an easy upgrade for this engine. Race engine builders looking to up the 5.0 liters power output past 600 hp should consider forged H-beam rods
The 5.0 liters hypereutectic pistons were designed by Mahle to be tough yet light and come in at 11:1 compression. Updates such as hard anodizing around the top ring groove and friction-reducing moly coating are incorporated to help extend piston life under hard load. On the top end the valve reliefs are fly cut to tight tolerances.
Photo Credit: Livernois Motorsports
The other pride point after the variable valve timing is the 5.0-liter cylinder heads. According to the engine team, the intake valves flow 4 percent better than the GT500 head and better than the old D3 NASCAR head. The 5.0-liter combustion chamber is a well-balanced design featuring two 37 mm intake valves and two 31mm exhaust valves. Intake ports are form a vertical shape and measure 193cc, exhaust ports are round and measure 37mm. Because the engine uses such small valves, the valvetrain is designed to be very compact. Roller finger followers actuated by the cams activate tiny rocker arms. Beehive valvesprings keep tension on the valves and seals the combustion chamber.
Photo Credit: Livernois Motorsports
The 5.0-liter cams provide max lift at 12mm (0.472-inch) on the intake and 11mm (0.432-inch) on the exhaust side. The VCT system can advance or retard the cams from their initial position from 81 degrees to 131 degrees.
The new 5.0 Liter engine features a plastic intake that in past models has proven to be lighter, cheaper to produce and delivers a cooler air charge. Composite intakes are now a given in naturally aspirated applications and a single 80mm single bore throttle body feeds 8 equal length intake runners. Aluminum spacers hold the fuel rails in place as the feed eight high flow injectors
Short tube tuned twin T-style headers were developed by the 5.0 liter engine team to maximize the unique exhaust pulses from the Ti-VCT engine. While the Job 1 cars feature the tubular headers we hear a cast exhaust manifold is in the works for a mid-year update.
With the new 5.0 liter engine already peaked out at efficiency, many will debate the need to add boost to such a great package. But with the engine already designed to handle boost as part of Ford’s EcoBoost future, it will be interesting to see how much the engine can take with a aftermarket supercharger or turbo. It’s evident that Ford Racing has already perfected the low boost supercharger application. Its now up to the various Mustang tuners to attempt a high boost R&D program on an engine that is totally different than the old 3 and 4-valve modular engines.