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U.S. Gear Power Chip - 4-Wheel & Off-Road Magazine

You've heard the claims made by aftermarket computer chip manufacturers for years: 30 hp, 40 hp, and even 50 hp simply by altering your vehicle's timing and fuel calibrations, both controlled by the vehicle's computer. That's why we were doubtful when Steve Deitsch at Off Road Unlimited called to tell us about a U.S. Gear Power Chip for Ford 7.3L Power Stroke turbodiesel engines.

131 9903 U S Gear Power Chip 1996 Ford F350 Front Three Quarter Camper Trailer Shot Photo 29554808

We told him, "Stevie, do a rear-wheel dyno test at an independent place, change the chip, and test it again-then we'll see if we're interested in an article." A week later, he called again and said we weren't going to believe what they'd found: a bigger power gain than U.S. Gear claimed in its brochure and a significant increase in fuel economy. "We'll be right over."

The Power Chip plugs into the diagnostic port of the Ford Powertrain Control Module (PCM) and recalibrates it to maximize vehicle performance by altering the air/fuel mixture, turbo boost, and automatic-transmission shift and lock-up points. It was designed with towing heavy trailers in mind, but the added power and fuel economy is welcome under any circumstance.

The truck used for our test was a lifted '96 F-350, which the owners, Jeff and Nancy Burns, used frequently to haul a two-horse trailer. The 35x12.50R16.5 tires with stock axle gears had taken a lot of oomph out of the Power Stroke, and the owners were looking for a simple way to improve the power. Eric Garding at Off Road Unlimited had the PCM pulled, the Power Chip plugged in, and the truck back on the road in a matter of hours, and the power gains speak for themselves. What no one expected, however, was for fuel economy to jump from 14 mpg to 17 unloaded and from 11 to 14 loaded!

Power Gains We're always skeptical when we hear of grandiose power gains from simple modifications, so we insisted this truck be tested at an independent facility. Bob Jennings Dyno Shop was one of the first companies in Southern California to use a rear-wheel dyno for tuning in addition to fact-finding. The truck was tested the day before the U.S. Gear Power Chip was installed and then again after a few thousand miles had been clocked with the chip in place. The power increases were beyond what U.S. Gear claimed and are validated every time the throttle is mashed.

RPM Stock HP With HP Stock Torque With Torque HP Power Chip Gain Torque Power Chip Gain 2,000 150 230 80 394 603 209 2,500 165 238 73 347 500 153 3,000 175 240 65 306 420 114 PhotosView Slideshow Garding pulled the fender trim and inner fender panel down on the driver side of the truck to gain access to the PCM. The computer slides into a port on the firewall between the brake master cylinder and the fenderwell, and it's held in place with a retaining seal. The ground wire and multipin connector must also be removed. The instructions detail handling the PCM and taking necessary precautions such as removing the coatings from the control-board connector with a special tool provided by U.S. Gear. The dust created by cleaning this port must be removed from the PCM. The Power Chip is installed by being pushed into the diagnostic port. It's recommended to put a piece of tape over the chip to hold it in place while the PCM is slid back into the truck. To use the diagnostic port in the future, the Power Chip must be removed. The chip learns your driving style and customizes the engine and transmission calibrations to this style. We felt an immediate increase in power but drove the truck for over a week before testing rear-wheel power on the dyno.