Westen Champlin Builds A Cummins Swapped Rolls Royce Phantom

What happens when a blown-up luxury icon meets a legendary diesel workhorse? Westen Champlin decided to find out by building a Cummins-swapped Rolls-Royce. Westen’s ambitious project started with a broken Phantom and a vision to create something utterly unique, reliable, and capable of rolling some serious coal.

Out With The V12, In With The Cummins

The project began with a Rolls-Royce Phantom suffering from a dead 6.7-liter V12 and failed air suspension. Westen declared the mission early: “We are going to rip this V12 out of here and we’re going to Cummins swap this Rolls-Royce.” Thanks to NextGen Parts Place, a running 5.9-liter Cummins donor engine was sourced. After a challenging but successful extraction of the massive V12, the initial mock-up showed promising results. The Cummins looked like it would fit surprisingly well, potentially even retaining its mechanical fan.

A Mid-Build Power Upgrade And Fab Work

While the original 5.9-liter was sent off for its transformation, the team used it to fabricate custom motor mounts and a transmission crossmember, permanently mounting the drivetrain. Wiring help came from Diesel Conversion Specialists (DCS), a company Westen recalled as “The first ever person that helped us out on a build was DCS, like five years ago on the Fuminss.” An Airlift Performance air management system was also installed, though progress hit a snag when they discovered a blown front air strut.

ECU Nightmares and First Fire

Getting the Cummins to run proved to be the biggest hurdle. After confirming wiring and fuel delivery from the AirDog lift pump, the team battled a series of ECU problems. Westen admitted his mistake: “I bricked the ECM we were using yesterday.” Several subsequent ECUs failed due to shorts or internal issues, compounded by the factory SKIM security system needing bypass tuning. Finally, a fourth ECM brought the beast to life, leading to the crucial first start-up.

The First Drive Of The Cummins-Swapped Rolls-Royce

With the engine running, Westen couldn’t resist attempting the first drive, even with no brakes and a collapsed front suspension. After maneuvering the massive car out of the bay, he celebrated: “I made it outside! This is badass.” Although barely drivable, the car did move under its own diesel power. Westen summed up the milestone: “Guys, in case you’re wondering what all has been done with the Rolls-Royce, it runs and it drives.” This wild Cummins-swapped Rolls-Royce project is far from finished, but the proof of concept is officially rolling smoke.