Diesel engines love air. It’s almost like they can’t get enough of it. Chances are pretty good that if your truck is still sporting the stock turbo, it’s probably not making as much power as possible. In the June 2014 issue of Diesel Power (“6.0L Weekend Warrior
”), we introduced you to an 2007 Ford F-250
6.0L Power Stroke that received a full array of upgrades from the folks at Banks Power. The fishing boat tow rig was equipped with water-methanol injection, a larger (dual exit) exhaust system, an advanced exhaust brake system, a programmer, a larger intercooler, bigger boost tubes, and a Ram-Air intake—but we couldn’t leave well enough alone.
The previous upgrades greatly improved the performance of the Ford Super Duty, increasing its rear-wheel horsepower to 402 hp and 793 lb-ft of torque. Testing showed the upgrades really enhanced the acceleration of the truck when it was unloaded, and also while towing a weighted trailer on a steep, 8-percent grade. Now that Banks has a new direct-swap turbo upgrade for the 6.0L Power Stroke, we decided to see what all the previous upgrades could achieve with the assistance of even more air. Follow along as the folks at Banks ditch the factory turbo for a higher-flowing aftermarket version.
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| The Banks/PowerMax turbo uses nine movable vanes that close up around the turbine wheel outlet during low engine speeds to minimize lag. The vanes are controlled by a system that can infinitely adjust them for consistently smooth operation.
Taking It In
Banks is now selling the Garrett GT3788VA-based Banks/PowerMax turbo, which uses a 63.5mm compressor wheel inducer that moves a lot more air than the stock 59mm unit. This size difference allows the turbo to flow about 70 pounds per minute (1,000 cfm) compared to 60 pounds per minute (850 cfm) from the stock turbo. The GT-series turbo utilizes Garrett’s patented Advanced Variable Nozzle to minimize lag and has much better top-end flow characteristics when combined with the larger intercooler, 3½-inch boost tubes, and the intake manifold upgrade from Banks.
The Big Exit
The exhaust side of the turbo has nine variable vanes to maximize the effectiveness of the exhaust gases pushing through the turbine wheel. They are controlled by electro-hydraulic actuation using a proportional solenoid that allows infinitely variable control for smooth operation. Garrett says this design significantly increases turbine efficiency over stock by improving performance at all engine speeds. Thanks to the dual exhaust system that was recently installed, the new turbine also has the advantage of less backpressure thanks to the Banks Monster system’s free-flowing design.
The Turbo Swap
Since the GT3788VA was designed as a direct replacement for the 6.0L Power Stroke, the installation is not as difficult as you might think. Removing the factory unit only required moving some wires and unbolting it from the engine, intake and exhaust, and coolant and oil systems. After that, the new turbo was seated on the pedestal in the valley, hooked to the oil and coolant supply lines, and connected to the up-pipes and downpipe. Then, after the boost tube and intake were connected, it was just a matter of snapping a few wires, such as the one used for the turbo controller, back into place.
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You shouldn’t be afraid to upgrade your own turbo—it may not be as hard as you might think. A Banks Power technician dove in and didn’t use any specialized tools to pull the factory turbo from the engine bay.
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This is what the 6.0L Power Stroke engine looks like without its turbo in place. On the left is the downpipe that connects the turbine outlet to the exhaust system, and to the right of it is the termination point of the up-pipes that brings exhaust gases into the turbo from the exhaust manifolds. Also notice the oil return drain. Banks’ technicians put the red plastic caps in place to ensure no debris would make its way into the engine or the exhaust system.
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Mounting the Banks/PowerMax turbo was fairly easy and even put a smile on the technician’s face when the turbo settled into its new home after less than five minutes of wrangling.
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After the O-rings on the connection points were greased, the new oil supply line was installed.
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A torque wrench was used to make sure all the mounting bolts and exhaust connectors were torqued to the manufacturer specifications.
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In the June ’06 issue of Diesel Power, this ’07 Super Duty received a number of underhood upgrades, including big, 3½-inch intercooler pipes. After the turbo was tightened into place, the boost tube that leads to the Techni-Cooler intercooler upgrade was connected to the outlet of the new turbo.
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The new turbo was reconnected to the Banks Ram-Air system that was installed as part of the Big Hoss bundle. The new turbo is able to take full advantage of the free-breathing design of the cold-air intake.
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Once the Banks/PowerMax turbo was mounted and connected to the intake, exhaust, coolant lines, and oil supply, it was wired into the engine computer using the same harness utilized by the stock turbo. Then, the underhood wiring was snapped back into place above the firewall.
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With the turbo in place, the underhood transformation of the 2007 Ford F-250
Super Duty was complete…for now. Along with the new turbocharger, the truck has a Double-Shot water-methanol injection system, a Techni-Cooler intercooler, 3½-inch boost tubes, a Ram-Air intake, a High-Ram intake manifold, a SpeedBrake smart exhaust brake system, a Monster Exhaust dual-exit exhaust, a Six-Gun tuner, and an iQ 2.0 touchscreen controller and display.
The first set of dyno tests with the new turbo upgrade was performed with the Banks Six-Gun set for maximum output and without use of the water-methanol injection system. This setup resulted in 391 hp and 670 lb-ft of torque at the rear wheels
compared to just 270 hp and 441 lb-ft of torque stock. The second set of dyno tests was performed with the Double-Shot water-methanol system and the Six-Gun set for maximum output. These settings resulted in the biggest gains, with output jumping to 454 hp and 787 lb-ft. This is a whopping 184 hp and 346 lb-ft of torque more than the truck made in factory form.
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On the dyno behind the Banks Power garage, the new Banks/PowerMax turbo was put to the test. When the tires stopped spinning, the charger helped the truck make 454 hp and 787 lb-ft of torque at the rear wheels. That’s 184 hp and 346 lb-ft of torque more than the truck could produce in stock form.
| 2007 Ford F 250 6 0L Power Stroke Garrett PowerMax By Banks Power Horespower Dyno
| 2007 Ford F 250 6 0L Power Stroke Garrett PowerMax By Banks Power Torque Dyno
After the truck was done spinning the dyno drum, it was taken out on the road for some real-world testing scenarios. The F-250 was hooked up for some 0-to-60-mph blasts with a loaded trailer for a combined weight of 19,290 pounds. When the truck was completely stock, it took a leisurely 26.9 seconds to get up to highway speed. However, with the Banks/PowerMax turbo, Big Hoss bundle, and Double-Shot water-methanol injection system, acceleration was cut down to just 15.8 seconds. That’s an 11.1-second improvement!