For all the virtues of Ford's new F-150, extreme performance is not one of them. It's a smooth, quiet truck with surprisingly good handling, but it's a bit short on power. And with no new Ford SVT Lightning in the works, what's the alternative?For those Ford guys who want to unleash the racehorse in their truck, check out Kenne Bell's TopGun. Named for those hot-shot F-14 Tomcat pilots who go ballistic right off the deck of an aircraft carrier, TopGun gives regular guys a fighting chance at some serious cockpit action. With 462 lb-ft of torque on tap, this pickup drives like a carrier's steam-powered catapult.
At the heart of TopGun is a 5.4L, 32-valve Triton V-8, armed with a Kenne Bell blower. Even in stock form, the Ford powerplant features include a whole menu of technological advances, like Variable Cam Timing, designed to match performance demands, and Charge Motion Control Valves (CMCV) for improved air management.
To better control this power, the engine has a new torque-based, electronic throttle control (throttle-by-wire) system. In addition to these improved system controls, the electronic throttle allows engineers to tailor the throttle to specific tasks. For instance, in 4x4 low-range, there's a dedicated accelerator response strategy for challenging or slippery conditions. Unfortunately, while that feature may be of value if you're using your new F-150 to tow a trailer or haul a hefty load, it made adding the Kenne Bell blower a lot more challenging.
"That new drive-by-wire electronic throttle interacts with everything," explains Jim Bell of Kenne Bell. "Reprogramming the codes was a pain." It also means that he was limited to only two boost levels on the blower: six and nine pounds of boost. Anything higher than nine pounds and the drive-by-wire senses an excess of airflow and pulls back the throttle to protect the engine.
Fortunately, modifying the fuel side was somewhat simpler for Kenne Bell. Some Ford vehicles use a return line, which can create problems with octane loss when fuel delivery is increased for the blower (due to increased heat from friction at the orifices). The new F-150 doesn't have one though, so all Bell had to do was install larger, 42-pound injectors and his Boost-a-Pump for upping the fuel flow.
Rather than putting in a larger fuel pump, the Boost-a-Pump increases flow by simply bumping up the voltage on the fuel pump from 12.5 to 16 volts when a pressure switch is activated under boost. At cruising speed, however, the pump flow remains stock, so there's no sacrifice of fuel economy. Since the pump works by pulsing, Bell says there's no problem with the extra fuel pressure.