The original 6.7L Scorpion was not just a calibration play. Ford built an engine around airflow, combustion support, and structure. The hot-V layout moved the exhaust into the valley and routed boost through a very large intake path, including valve-cover intake plenums that add swirl into the ports. The valvetrain is unusually clever too, using two lifters to run four pushrods and four individual rockers per cylinder, which avoids the uneven valve action you get with bridge-style systems. On the turbo side, Ford went after a very wide operating range with a dual-compressor, VNT, wastegated unit, but that design also shows the tradeoff between response ambition, rotating mass, and long-term durability. Underneath it all is a serious diesel foundation: compacted graphite block, six-bolt mains, forged steel crank, cracked-cap rods, and oil-cooled pistons. That combination is why this engine mattered in the horsepower war.
Gale Banks frames Ford’s 6.7L Scorpion as the engine that helped ignite an earlier diesel pickup horsepower war.
In March 2010, Ford announced the new 6.7L at 390 horsepower at 2,800 RPM and 735 lb-ft of torque at 1,600 RPM. GM responded in June with 397 horsepower and 765 lb-ft, beating Ford by 7 horsepower and 30 lb-ft.
Ford had already certified a second calibration, however. In August 2010, it announced an increase to 400 horsepower and 800 lb-ft. Banks points to Ford’s original dyno curves, which appeared to have flattened torque and clipped horsepower, as evidence that Ford may have deliberately held the stronger calibration in reserve.
The original Scorpion uses an ambitious hot-V architecture. Instead of placing the intake in the valley and exhaust manifolds outside the heads, Ford reversed the arrangement. The exhaust manifolds and turbocharger sit in the valley, while the intake ports are positioned on the outside of the cylinder heads.
Charge air follows a long path through the engine compartment. After entering the intake system and turbocharger, compressed air travels through a liquid-cooled charge-air cooler, returns through the throttle and EGR mixing section, enters the intake manifold, and ultimately passes through the valve covers before reaching the intake ports.
The hot-V layout shortens the exhaust path to the turbine, potentially improving turbo response. The tradeoff is considerable intake volume that must be pressurized before the engine can cleanly support additional fueling.
One of the Scorpion’s most unusual features is that its valve covers are functional parts of the intake manifold.
Boosted air enters the valve covers and is routed toward intake ports on the outside of the cylinder heads. The ports direct the incoming charge sideways as it enters, helping generate swirl as air moves into the cylinders.
Banks considers the arrangement clever but notes its thermal challenges. The intake system is positioned near hot exhaust components in the valley while the valve covers themselves are exposed to heat from the valvetrain and engine oil.
Each cylinder uses four rocker arms and four pushrods but only two lifters and two cam lobes.
Rather than using a conventional bridge that allows one rocker to operate two valves, Ford gives each valve its own rocker. Banks sees this as an advantage because traditional bridge arrangements can create unequal valve movement when spring forces are not precisely matched.
The stamped-steel rocker arms incorporate the pushrod cup, valve contact surface, and pivot geometry. Lubrication comes from a spray bar with four small outlets per cylinder.
Large roller tappets use needle bearings and are held in alignment by a guide cassette. Ford also incorporated hydraulic lash adjustment into the system, creating a zero-lash valvetrain capable of operating comfortably beyond the engine’s 2,800 RPM horsepower peak.
The original Scorpion uses an unusual Garrett dual-boost VNT turbocharger with a wastegate and two compressor sections operating on a common shaft.
The exhaust manifolds and turbine feed passages are relatively small to maintain exhaust velocity and accelerate the turbine quickly. The tradeoff is increased restriction and exhaust backpressure.
The turbo combines variable-nozzle turbine control with a separate vacuum-operated wastegate. Because a diesel does not naturally produce the required manifold vacuum, the engine also uses a mechanically driven vacuum pump.
On the compressor side, there are two separate inlets feeding a dual-faced compressor wheel. The concept was intended to provide useful compressor performance across a broad range of shaft speeds, boost pressures, and airflow demands.
The dual-compressor arrangement places substantial rotating mass far outboard on the turbo shaft. Ford initially supported the assembly with ceramic ball bearings.
Banks challenges the assumption that ball bearings automatically produce dramatically faster turbo response. Based on testing at Gale Banks Engineering, he argues that rotating mass has a greater effect on response than bearing type.
Ford experienced turbo bearing warranty problems during the early years of the Scorpion. The bearing design was subsequently changed, and by the 2015 model year the original dual-compressor turbocharger architecture had been replaced.
For Banks, the short production life is particularly notable considering the engineering, development, tooling, and manufacturing effort required to bring such an unconventional turbocharger into production.
One component Banks particularly appreciates is the turbine outlet casting, known within Ford as the Cobra Head.
Its geometry draws from a NACA-style aerodynamic profile to make a tight 90-degree turn while minimizing flow loss.
The outlet is also double-walled, creating a thermal barrier between the hot exhaust passage and surrounding components. This helps reduce heat transfer toward areas such as the firewall while maintaining a compact exhaust path.
The Scorpion’s oil pan is an unusually complex casting that integrates several lubrication passages.
Oil is drawn from the sump into a gerotor pump, then routed through cast-in passages to the oil cooler and oil filter before being distributed through the block and cylinder heads. The lubrication system also supplies the turbocharger.
The engine uses a compacted graphite iron block, six-bolt main bearing structure, forged-steel crankshaft, tangless bearings, and forged powder-metal cracked-cap connecting rods.
The pistons are gallery cooled. Oil jets spray lubricant into internal passages within the piston crowns to remove heat during operation.
Taken together, these features show how extensively engineered the original 6.7L Scorpion was. Banks views the first-generation engine as an ambitious foundation for the later versions of Ford’s 6.7L Power Stroke and a fascinating starting point for comparison with the modern engine.
