During a phone call from Stephen Clarke of Bully Dog Industries, up in Aberdeen, Idaho, he shared with me some performance dyno numbers pertaining to the Bully Dog Power Pup Downloader and nitrous oxide systems for the Chevrolet Duramax 6.6L Diesel. We made arrangements for him to drive the Bully Dog Chevy Duramax down to SoCal for some serious dyno time.
About the Bully Dog Power Pup Downloader
The Power Pup Downloader is a computer power program capable of producing 50, 70, or 95 hp, with the ability for the serious off-road enthusiast to upgrade to 150 additional hp.
The Power Pup also gives the driver the ability to remove the speed limiter on the '02 and '03 Duramax, and the ability to adjust the speedometer for different sized tires.
The downloader contains OBD-II functions to scan and erase engine codes. The customer can also purchase a 150 additional hp code from Bully Dog to be imported into the existing Power Pup unit. An optional dual-stage nitrous installation kit can also been plumbed into the system for that additional instant neck-snapping torque and power.
To handle the Duramax's increase in horsepower, it is recommended to install the Bully Dog Transmission Upgrade kit. This kit consists of additional clutch discs to be installed with certain clutch packs. A valvebody will match transmission fluid pressures and shifts with the torque converter and increased horsepower.
We called the team at Brothers Performance in Corona, California, known for its truck, engine, and suspension components, to reserve some dyno time on Brothers Dynojet 248C treadmill.
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 After getting the burly Chevrolet...  After getting the burly Chevrolet Duramax 6.6L centered on Brothers' Dynojet 248C Dynamometer drum rollers, it was cinched down. |
 The Bully Dog Edition Chevy...  The Bully Dog Edition Chevy Duramax has become the company's mule for R&D projects and demonstrations. |
 At first glance, the Duramax...  At first glance, the Duramax Diesel appeared pretty tame, but the more we scanned the engine and compartment, we began to notice some additional horsepower treats. |
 Of all the additions to the...  Of all the additions to the engine that caught our eye, the dual NOS solenoids really stood out, which means only one thing -- excitement. Bully Dog's Bully Kicker Kit includes a 15-pound nitrous bottle complete with size 6 AN lines and features a bottle pressure gauge and two toggle and pressure switches. The Dual Shot Kit also includes both a high-performance, small 0.063 solenoid and a larger 0.125 solenoid. The Bully Dog nitrous kits are dry systems. To get proper nitrous gains, a match up with fuel flow is required. The kit coordinates the truck's diesel fuel input and engine displacement. |
 To increase airflow into the...  To increase airflow into the Duramax air intake, Bully Dog developed a serious air intake system and filter, as well as RFI (Rapid Flow Induction). The RFI air cleaner and shroud also prevents air buffeting and hot-air buildup. Bully Dogs' 4-inch-diameter stainless steel exhaust system increases the exhaust gas volume, which exhausts with less restriction. |
 All of the electronic leads...  All of the electronic leads and probes were connected to the Duramax, and the hood was closed to create a more real-world environment during testing. |
 Bully Dogs' Stephen Clarke...  Bully Dogs' Stephen Clarke pre-programmed the Power Pup with the Duramax computer prior to the multiple dyno pulls to determine the torque and horsepower increases. |
 Robert, a Brothers Performance...  Robert, a Brothers Performance technician, programmed the Dynojet computer prior to the first pull. |
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 To capture and establish the...  To capture and establish the factory torque and horsepower data, Robert watched the rpm increase as he mashed the throttle after the Dynojet dumped a load on the Duramax during the baseline pull. |
 Referring to the computer...  Referring to the computer monitor, Robert and Stephen checked out the baseline dyno result, which was 248 hp to the rear wheels. |
 Prior to a multitude of dyno...  Prior to a multitude of dyno pulls at different horsepower settings, Stephen slid behind the wheel and programmed the Power Pub. |
 After a couple of Power Pub...  After a couple of Power Pub pulls, the results were evaluated. A 70hp download resulted in 303 hp, then with a 150hp download, the results were 403 hp. |
 For some real entertainment,...  For some real entertainment, Stephen released the horsepower valve of the nitrous oxide bottle. |
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 Robert observed the Duramax...  Robert observed the Duramax vital signs as he glanced at the Bully Dog boost and exhaust pyrometer gauges encased in the A-pillar molded pods. The Power Pup was programmed to induce a 150hp download with some extra boost injected from the Bully Nitrous Kicker system. The potent combination almost spun the tires off the rollers. |
 After the final grunt pull,...  After the final grunt pull, with the 150hp download from the Bully Dog Power Pup and the Bully Nitrous Kicker system, the results were very impressive -- 492 hp. |
 Here is Brothers Performance...  Here is Brothers Performance Dynojet Model 248C's baseline pull at 248 hp (1), and here is the pull with the Bully Dog Power Pup 70hp download equalling 303 hp (2). |
 Here is a picture of the Brothers...  Here is a picture of the Brothers Performance Dynojet Model 248C Bully Dog Power Pup 150hp download equaling 403 hp (3), and the Bully Dog Power Pup 150hp download with Bully Dog Kicker Nitrous Oxide equalling 492-plus hp (4). |