A Vintage Jeep CJ2A Gets Transformed With a Turbocharged Kubota Diesel

When Matt Branstetter decided to drop a Kubota V2203 turbodiesel into his 1946 Willys CJ2A, he knew he was tackling something special. The CJ2A holds a unique place in off-road history as the first civilian Jeep produced after World War II, rolling off the Toledo assembly line from 1945 to 1949. These rigs originally came equipped with the legendary “Go Devil” L-134 flathead four-cylinder engine, which produced a modest 60 HP and 105 lb-ft of torque. While that powerplant earned its reputation for reliability during the war, it wasn’t exactly known for setting the world on fire performance-wise.

The Go Devil engine served its purpose well enough for its era, but modern wheelers often find themselves wanting more grunt from these vintage machines. That’s where engine swaps come into play, and Matt’s choice of the Kubota V2203 turbodiesel makes perfect sense for several reasons. This industrial four-cylinder diesel delivers significantly more torque than the original flathead, which translates to better low-end pulling power for technical terrain. The turbocharger adds even more punch, giving this classic CJ the kind of torque curve that makes rock crawling and hill climbing much more manageable.

Diesel swaps have become increasingly popular among the off-road community, especially for older rigs that see serious trail duty. The fuel efficiency alone makes long-distance wheeling adventures more feasible, and diesel engines typically offer better longevity under heavy use. Matt sourced his conversion parts from Overland Diesel, a company that specializes in making these swaps as straightforward as possible for home builders.

The transformation goes well beyond just bolting in a new motor. Matt had to modify the transmission tunnel to accommodate the different engine dimensions, though he admits he probably went a bit generous with the sizing. The exhaust system currently runs a simple 2" straight pipe setup, which he notes sounds good without highway drone. The turbocharger and associated piping required careful routing to fit within the CJ2A’s compact engine bay.

Inside the cab, Matt upgraded the instrumentation to match the new powerplant’s requirements. The gauge cluster now includes a pyrometer for monitoring exhaust gas temperatures, a tachometer, oil pressure, and water temperature gauges. The speedometer needs replacement, and he’s planning to add a fuel gauge for better range awareness during trail runs. The glow plug system gets its own switch and wait light, though Matt mentions the engine fires up easily even without using the glow plugs in moderate temperatures.

What makes this build particularly appealing is how the diesel engine transforms the character of the CJ2A while maintaining its vintage appeal. The original Go Devil was known for being gutless at highway speeds, but the turbocharged Kubota provides much better road manners for getting to and from the trails. The low-end torque also means less clutch slipping and easier navigation through technical sections where precise throttle control matters.

Matt’s approach reflects the practical mindset many wheelers bring to their builds. Rather than chasing maximum HP, he focused on creating a reliable, capable machine that maintains the CJ2A’s classic aesthetic while delivering modern performance.

This conversion demonstrates how classic off-road iron can be updated for contemporary use without losing the character that made these machines legendary among enthusiasts.