The Big Hoss Bundle works because it treats the engine like a complete air system. We start by getting cooler, pressurized air from the front of the truck into the turbo with the Banks Ram-Air Intake System. Then the Big Head wastegate actuator increases boost, while the Techni-Cooler charge air cooler and larger boost tubes reduce restriction and deliver a colder, denser charge to the engine. On the exhaust side, the Banks Monster Exhaust System cuts backpressure so the engine can push spent gases out easier. The Six-Gun diesel tuner adds adjustable fueling, and the in-cab screen lets you monitor boost, exhaust gas temperature, and engine and transmission temperatures while changing power levels. On this 2003 Duramax, that package added 155 horsepower and 385 lb-ft, which is why the truck feels like a completely different machine.
The video centers on upgrading Tara's 2003 Chevrolet Duramax diesel with Banks' Big Hoss Bundle to deliver the extra horsepower and torque the truck needed. The package shown includes the Six-Gun diesel tuner, a Techni-Cooler charge-air cooler, larger boost tubes, the Big Head wastegate actuator, a Monster Exhaust with Diesel Duals, and an optional Banks Ram-Air intake system. Before the installation begins, Gale lays out the airflow strategy behind the package and explains how each component contributes to increased engine output.
Gale's intake-airflow lesson begins with the basic diesel performance principle that more air allows more fuel to be burned, which in turn produces more power. He presents the Banks Ram-Air intake as the first step in that process. According to the explanation in the video, the system draws air from the nose of the truck and routes it through ducting to the turbocharger in a cool, pressurized form. The goal is to improve the quality and delivery of incoming air before any additional boost or fueling changes are made.
Once air reaches the turbocharger, the next objective is to increase the amount of air being forced into the engine. Gale explains that Banks uses its Big Head actuator to spin the turbo harder and raise boost pressure. That added boost then passes through the intercooling stage, where the Techni-Cooler charge-air cooler is intended to reduce airflow resistance while lowering charge-air temperature. In the sequence described, the system is designed to deliver a denser, high-pressure, cooler air charge into the engine, supporting the additional fuel commanded by the tuner.
After covering the intake and boost side, the video shifts to the exhaust system. Gale remarks that the factory-style setup could be improved substantially and states that the goal for this combination is to reduce backpressure to zero. To address that, the truck receives a 4-inch Banks Monster Exhaust system fitted with twin stainless 5-inch tips, referred to in the segment as Diesel Duals. The exhaust upgrade is presented as the final part of the engine's airflow path, complementing the intake, turbo, and intercooler improvements by helping the engine expel gases more freely.
A major part of the package is the electronic control and monitoring system. The Six-Gun tuner provides adjustable fueling levels, allowing the driver to vary horsepower output. Its interface is shown through a PDA-style display that acts as both a controller and an information window into the truck. The screen can display data from the sensors GM installed on the vehicle, giving the driver access to operating information from under the hood in real time.
The PDA system is described as more than a simple tuner control. In the demonstration, it is used to monitor exhaust gas temperature, engine temperature, transmission temperature, and boost pressure. It also allows the user to change Six-Gun power levels directly from the display. Gale notes that the software is exclusive to Banks and says it had been in development for two years before reaching the market. The emphasis in this portion of the video is on combining added power with driver visibility into key operating conditions.
The installation is framed as achievable for an experienced do-it-yourself owner with tools and help from a friend, with the suggestion that the full Big Hoss Bundle could be installed over a weekend. In the video, however, one of the Banks professionals completes the work in about seven hours. The reported result on Tara's Duramax is a gain of 155 horsepower and 385 lb-ft of torque in less than a day. Those figures are presented as the cumulative outcome of the intake, boost-control, intercooling, exhaust, and tuning changes working together as a system.
After the installation, the truck is described as handling like a dream while finally delivering the extra horsepower that had been missing. The segment concludes with Tara trying the upgraded truck and turning the Banks Power setting all the way up before taking it for a drive with Gale. Her immediate reaction is that the power comes in abruptly and noticeably, and she comments that the truck drives completely differently. Although it is still the same vehicle, the final impression is that the combined Banks upgrades make it feel like an entirely different truck.