In the aftermarket diesel performance industry, there are two types of shops. There are the middlemen and the re-boxers who buy parts from someone else and mail them to you, and then there are the builders.

At D&J Precision Machine, we don't just sell parts, we design, engineer, and manufacture them. At our facility in Cambridge, Ohio, we’ve built a reputation for pushing the Cummins platform to its absolute limit. Whether you are looking for a reliable daily driver or a 2,000+ HP engine, at D&J we deliver uncompromising precision.

Our Cambridge Facility

Quality isn’t something you should outsource. To ensure our components are the best in the industry, we’ve invested heavily in some of the bestCNC machines money can buy.

When you see a D&J billet valve cover, a set of our FSR pistons, or our custom rods, you’re looking at parts that were designed, engineered, and machined all under one roof. By keeping the manufacturing process in house, we eliminate the middleman errors that happen so often with other suppliers. We don't have to hope the parts are right, we know they are because we make them and thoroughly inspect them before they arrive at your door. 

The Core Philosophy

Most shops receive a block, send it to a machine shop, buy parts from a third party, and then assemble it. At D&J, we follow a strict workflow process.

• Engineering: We identify the weak points in factory Cummins components.

• Prototyping: We design solutions (like our Stage 2 heads or billet blocks) using advanced CAD software.

• Machining: Our CNC technicians turn raw materials into high performance parts.

• Assembly & Testing: Every engine is assembled by specialists who live and breathe diesel performance.

By controlling every step of the manufacturing journey, we can ensure that when a long block leaves our doors, it is ready to handle whatever boost, torque, and heat you throw at it.

Part of a Global Performance Family

While our roots are planted in Ohio, our reach is global. As a proud member of the Burnout Brands family, alongside other industry leaders like BD Diesel and Monster Transmission, we have the resources to innovate faster than ever before.

This partnership allows us to combine D&J’s specialized precision machining with a massive distribution and support network. You get the specialized attention of a custom machine shop with the stability and backing of the biggest names in the aftermarket diesel performance world. (And yes, Drew is still here and fully involved in the entire process.)

Ready to Upgrade Your Build?

Whether you need a billet timing cover or a full Executioner engine build, we have the tools and the talent to achieve whatever vision you have for your Cummins.