Upcoming Scorpion 6.7-Liter Diesel V-8
Our spies have caught a glimpse of Ford’s new in-house-designed 6.7-liter V-8 diesel engine under the hood of a Super Duty engineering mule. Code-named Scorpion, the new engine is expected to replace the Navistar-sourced 6.4-liter V-8 Power Stroke diesel engine in Ford's heavy-duty pickups by 2011.
In earlier spy photos of Scorpion-equipped test trucks, we wondered why the Super Duty mules needed raised hoods. Now we think we know the reason: The picture clearly shows a gigantic radiator used to cool the engine for extreme towing applications.
Ford increased the size of the radiator in the 2008 Super Duty, when the 6.4-liter V-8 diesel debuted, by 33 percent. Now, we estimate its surface area has increased approximately another 10 to 20 percent with the new radiator. It’s so large it apparently has to be canted backward to fit under the hood!
Our sources say the Scorpion will share several key traits with GM's revolutionary new light-duty 4.5-liter Duramax V-8 diesel engine. Intake and exhaust flow through the cylinder heads is reversed (relative to conventional diesel-engine design), with the exhaust exiting directly into dual sequential turbos sitting in the engine's valley. The Scorpion will also use lighter aluminum cylinder heads, abandoning the cast-iron heads found in today's 6.4-liter Power Stroke.
Power targets are said to be more than 390 horsepower and 720 pounds-feet of torque. Today's Power Stroke diesel is rated at 350 hp and 650 pounds-feet.
Scorpion fuel economy is expected to improve by 3 mpg or more versus the current Power Stroke. Helping the Scorpion's mileage will be a new six-speed automatic transmission, like the 2009 Ford F-150 has.