Kill Devil Diesel’s 6.7 Powerstroke Test Mule
What started as a worn-out work truck has become one of the most important tools in our research and development program.
A few years ago, we picked up an old cut-up work truck for a couple thousand dollars with a simple goal: create a dedicated platform for testing cylinder heads, camshafts, and engine combinations. Like many projects, it spent some time on the back burner while we focused on keeping up with engine builds and cylinder head orders. Once we got lead times under control and inventory on the shelf, we finally had the opportunity to bring the project to life.
Today, that truck has evolved into a development platform that allows us to test new products, gather real world data, and continue pushing Powerstroke performance forward.
Why We Built It
While the truck has become a serious race vehicle, its primary purpose isn't chasing elapsed times. Every component and every pass down the track is focused on development and data collection.
As the project progressed, we reached the limitations of the factory ECU and made the switch to a complete MoTeC engine management system with help from the team at S&S Diesel Motorsport. The additional control and data acquisition capabilities give us a much clearer picture of what's happening inside the engine, allowing us to make informed decisions during product development and testing.
The information we gather from this platform directly impacts future engine packages, cylinder head programs, camshaft designs, fuel system components, and other products we bring to market.
The Engine Combination
One of the most interesting aspects of the build is that it still uses the original 6.7L Powerstroke engine that came in the truck.
The engine was refreshed with new pistons, rings, and bearings before being upgraded with Carrillo connecting rods, our Jesel rocker arm conversion, a solid lifter setup, and one of our larger camshaft profiles.
This combination gives us an excellent baseline for ongoing camshaft development and allows us to perform back to back testing as we continue refining future offerings.
For now, we're still running factory cylinder heads. That decision was intentional. Establishing a baseline with stock heads gives us the opportunity to accurately measure the gains from our latest cylinder head development program, including our billet intake plenum package and fully ported head designs.
Fuel System Development
The truck is also serving as a proving ground for one of our newest fuel system innovations: our CP3 gear-drive conversion.
Fuel is supplied through S&S Diesel Motorsport 200% over injectors and a 14mm CP3 pump using DCR fuel system components. Unlike traditional belt-driven CP3 conversions, our system drives directly from the factory CP4 gear.
Eliminating the belt removes concerns about belt stretch, slippage, and long-term pump wear caused by belt tension while creating a cleaner and more compact installation.
The truck gives us the perfect environment to validate the durability and performance advantages of this setup under extreme conditions.
Turbocharger Testing
Airflow is currently provided by a Garrett 76mm ball-bearing turbocharger in a T4 configuration.
While many high-horsepower Powerstroke builds rely on compound turbo setups, we've chosen to spend significant time testing single turbo combinations to better understand their performance characteristics and optimize our future product offerings.
Additional testing is already planned, including evaluations of 72mm turbocharger combinations for applications such as 72 Fast competition classes.
Lightweight Chassis, Serious Potential
The truck's transformation goes far beyond the engine bay.
Through extensive chassis modifications and fabrication work completed with help from Nathannial DeLong and the team at Rudy's Performance Parts, the truck has shed nearly 3,000 pounds compared to its previous configuration.
What once weighed approximately 7,200 pounds now tips the scales around 4,500 pounds, dramatically increasing the vehicle's performance potential and making it an even more effective development platform.
Power is transferred through a 4R100 transmission utilizing our engine adapter package, creating a durable drivetrain combination capable of supporting future testing and growth.
Looking Ahead
In its current configuration, the truck is capable of producing an estimated 1,300 to 1,500 horsepower on fuel alone, with enough fuel and airflow available to support significantly more when nitrous is added.
But horsepower numbers aren't the primary focus.
The real value of this project is the data it generates and the opportunities it creates for future product development. Every test session helps us better understand engine behavior, improve component designs, and validate new ideas before they reach our customers.
What started as an old work truck has become one of the most valuable tools in our shop-a rolling laboratory that continues to help shape the future of Kill Devil Diesel performance products.