How High-Performance Racing Improved Remanufactured Cummins Engines: D&J Precision Machine Shares Their Journey
In Episode #540 of Race Industry Now, Jeff Hammond, NASCAR Crew Chief Champion and SiriusXM host, sat down with Drew Pumphrey, Founder of D&J Precision Machine, to explore the remarkable intersection of diesel engine remanufacturing and high-performance motorsports.
Hosted by EPARTRADE and SiriusXM, the conversation shed light on how racing technology and demands have transformed D&J’s remanufactured Cummins lineup — pushing traditional diesel engineering into a new era of innovation and power.
From Teen Tinkerer to Industry Leader
Pumphrey’s journey into diesel performance started at age 17, inspired by personal projects and competitive sled pulling. His early hands-on experience led him to Enterprise Engine Performance, where he honed his skills building Cummins engines and managing a full-scale machine shop.
Although originally destined to run his family’s Wendy’s franchises, Drew’s side projects building engines for former clients quickly escalated into something bigger. “I caught myself buying a CNC machine because we couldn’t find the parts we needed,” said Pumphrey. “That’s when I knew we were going all-in.”
Engineering Evolution Through Racing
Today, D&J Precision Machine operates out of a 30,000-square-foot facility, far beyond the 2,400-square-foot space it began in. What sets them apart is how their racing program directly fuels engineering advancements in their remanufactured product line.
By developing performance components like custom intake manifolds and forged connecting rods for competition use, D&J has been able to reverse-engineer durability, precision, and horsepower gains into their reman lineup.
“Diesel engines are misunderstood in racing,” said Pumphrey. “They’re not only powerful but surprisingly easy to maintain — if built the right way. Racing pushes us to find every possible edge in performance and reliability, and we bring that knowledge straight into our remanufacturing process.”
A Company Built by Passion
What began with a single employee now stands as a recognized brand in diesel performance, serving both racing professionals and everyday diesel drivers. D&J’s hybrid approach — combining R&D from motorsports with scalable production for consumer markets — represents the future of precision diesel engineering.
For more information, watch the full webinar here.
