Increasing Horsepower - From The Git-Go

You can lie to everyone but the dynamometer. OK, OK, you can lie to the dynamometer too, but dyno results have credibility that not even Johnny Cochran can dispute. Gale Banks Engineering, known primarily for its turbo engine upgrades, makes some pretty hefty performance promises so we wanted to test them. We had to know the exact power increase that the basic Joe Schmoe kit could produce.

We took our '01 Ford 7.3L turbodiesel to Banks for a get-more-power install and a before-and-after chassis dyno test. Before we get all uppity about how easy it is to gain extra horses, we need to tell you a little bit about how the diesel engine works. The diesel engine sucks in air and compresses it in the cylinder. Fuel is injected directly inside the cylinder as a fine mist and mixes with the incoming air as it is compressed. The heat generated by this compressing of the air/fuel mixture ignites the fuel, spontaneously creating engine power, heat, and exhaust gases.

The Banks OttoMind chip is calibrated to run the fuel/air mixture fuel rich into the Powerstroke's cylinder. The chip is not designed as a stand-alone upgrade, and for good reason. As the extra fuel causes the cylinders to produce more power, a greater amount of exhaust gas builds up in the downpipes (called backpressure), causing negative effects on power gains. Hand-in-hand, the chip and a larger-capacity exhaust allow engine performance gains and seat of the pants acceleration advantages.

Enter Banks' Git-Kit. The kit includes an OttoMind engine calibration module, a 4-inch Monster Exhaust tailpipe, a Dynoflow muffler, and a 5-inch polished tip. The kit will run you about $795, but the power numbers from the low-buck install will make it worth it. The best gain numbers were a 38hp increase and a 69 lb-ft torque boost from about 40 minutes of work.

No Mo' Go
New from Banks is its exhaust brake for diesel engines. The supplemental braking system assists in slowing, especially during steep highway decent. The brake utilizes a streamlined, turbo-mounted housing with a large butterfly valve. It works like this: When braking is necessary, the butterfly valve responds by closing, which allows backpressure to build after the turbine, forcing the engine to absorb power as opposed to creating it. This causes the vehicle's engine to slow, similarly to the way compression braking works in a gasoline engine.