8 Of The Wildest Cummins Swaps Of All Time

The internet is flooded with a seemingly endless sea of all sorts of engine swaps, from bold sky-bound LS-swapped airplanes to these less common LS-swap alternatives. While it's usually easy to take the cliche route and echo the old adage "just because you can, doesn't mean you should," we decided to take a more nuanced approach and really lean into the perspectives of the mad scientists who cook up these mechanical concoctions.

Specifically, we're zeroing in on eight of the wildest Cummins swaps we came across during our deep dive into diesel-powered ingenuity. Believe it or not, only one entry is a truck. The rest are cars — well, except for the last one. Wink, wink.

Remember, the key word here is "wild" — not fastest, quickest, most powerful, or practical. That said, what better way to kick things off than by starting with a very wild Lamborghini Gallardo with a 5.9-liter Cummins turbo-diesel swap.

We've already determined that the Lamborghini Gallardo is old enough for the restomod treatment, so why not swap the Lambo's factory 5.0-liter V10 for something with a bit more torque. And yes, an unmodified 5.9-liter 6BT Cummins inline-six would be down on horsepower, but this unit is far from stock.

This build was whipped up by 1 Way Diesel Performance, a shop based out of Nacogdoches, Texas. The shop's efforts hit the spotlight when the Italian coal-roller was featured in an episode of MotorTrend TV's "Texas Metal's Loud And Lifted" series. The project started out with a totaled Gallardo, and if you're thinking to yourself, "how bad could a salvage auction Lamborghini Gallardo possibly be," well, that question has already been asked and answered.

Impressively, the fellas at 1 Way were reportedly able to complete the project in just 3 months. In addition to rectifying the issues that caused the Gallardo to be totaled out by an insurance company in the first place, not to mention all of the fabrication required to mount the Cummins to the chassis, the crew also fully built the Cummins engine, outfitting it with beefier internals, a ported head, and upgraded injectors. The result is said to be approximately 1,000 horsepower.

The Mazda Miata is adored for its small size, light weight, and balanced nimbleness. Purists will tell you that its naturally aspirated four-cylinder is adequate, but there are plenty of folks with a thirst for more torque. Fortunately, there are plenty of options for such enthusiasts, including superchargers, turbochargers, and, of course, engine swaps. We've seen our fair share of Miata swaps, from K-series four-bangers to LS V8s, but rarely have we come across a Cummins-swapped example.

Needless to say, this Cummins 4BT-powered MX-5 is pretty unique in the world of Miata swaps, and that's coming from the folks who've indulged in the sweet sounds of a motorcycle-swapped Mazda Miata. This swap is quite a different beast, though. The 1000cc inline-four from a 2008 Honda CBR1000RR weighs less than 150 pounds, which is a whole lot less than the approximately 750-pound four-cylinder turbo-diesel. For reference, the weight of the Miata's factory 1.6-liter four-banger is less than ⅓ of the 4BT's.

We could marvel over the mechanical feats this Miata represents and talk about how the shop incorporated stiffer Eibach springs, a transmission from a 1999 Ford F-250, along with an Exedy clutch for a Mustang and custom driveshaft bolted to a Ford 8.8-inch rear differential. But one of the coolest aspects of this build is the fact that Pistonhead Productions was able to use its efforts to donate thousands to the automotive shop program at its local high school. For context, the shop took in donations to complete the project as a means of inspiring young minds, and all of the leftover funds were donated. Putting together an awesome build while also inspiring the youth? That's a win-win.

A couple of months ago, our very own Brad Brownell boldly declared that a bone-stock MK4 Toyota Supra kind of sucks to drive. While Brownell suggested bolt-on solutions, such as wheels, suspension mods, and "mild" engine upgrades, Ashley Whitsey's Supra takes things to a whole other level with a Cummins 6BT swap.

We completely understand it if you're scratching your head, wondering why someone would forgo the Supra's legendary twin-turbo 2JZ inline-six for a heavier Cummins turbo-diesel. At the same time, it does work with the lifted, baja-like aesthetic of his particular build. It's akin to buying a Toyota Supra from an off-road dealer in the "Need For Speed Payback" video game, and then buying an engine upgrade that seems to cost much more than it's worth.

If it sounds like we're being critical, we're not. We would absolutely love to take this thing for a spin. When it comes to the numbers, a stock 2JZ made 320 horsepower and 315 pound-feet of torque fresh from the factory, while a stock 6BT was rated at 250 horsepower and 620 pound-feet. There are certainly easier ways to nearly double the torque of a stock Supra, but not too many are as wild as this swap. 

Another 4BT Cummins swap is on deck, but this time around, it's for a first-generation Chevy Camaro. How's that for changing things up? It's not just a half-running cruiser either, and it's actually used as a drag car. Yes, the burnouts are an absolute riot. Fortunately, the builder has footage of it at the drag strip, which was uploaded to the Jrodcummins YouTube channel.

How well does it work? It ran 7.97 seconds in the ⅛ mile, which is respectable. The Cummins itself has been worked over with pistons from a marine application Cummins, cams, springs, and head studs, along with bigger injectors and a Lightning turbocharger. The builder resourcefully retained the factory frame mounts, fabricated engine mounts, and customized the original crossmember.

If the notion of diesel-powered Camaros tickles your fancy, you'll be pleased to know that we came across quite a few such projects, including second-generation and third-generation Camaro Cummins swaps. Although exact details on the incoming seventh-generation Camaro are still sparse, we think it's safe to say that it won't offer a diesel powertrain.

A Cummins swap in a truck is inherently less wild than any other vehicle type. As such, the next build on this list is actually the only truck to make the cut, and rightfully so, as it's about as wild as it gets. In fact, while speaking to Ridiculous Rides, Kymera creator Gregg Hills from FourFabb said, "there's mild, wild, and then Kymera."

If you're particularly passionate about trucks and turbo-diesels, then chances are you probably already know all about this Kymera Colorado build. Otherwise, just look at the name: "Kymera" Colorado Cummins. The exaggerated alliteration is a perfect reflection of its ethos. Hills speaks to this directly, saying "the whole point of this is just to be over the top." And over the top it is. For starters, it features a chopped roof with a custom sawblade roof rack.

Additionally, its 5.9-liter Cummins turbo-diesel is said to pump out around 650 horsepower, which seems modest compared to its tenaciously capable Fox Racing suspension setup. On top of that, it's got front and rear steering, because, why not? Yep, it sure seems like the Kymera is the perfect tool to conquer any off-roading endeavor.

Staying under the General Motors umbrella brings us to our next wild Cummins swap: a 1950 Cadillac two-door dubbed "Nightmare.". It is, in our humble opinion, an absolute show-stopping head-turner. And, just as impressively, it's got the mechanical goods to back its outstanding appearance. Seriously, we highly recommend watching this AutoMotoTube video to see it for yourself. 

Making it all come together is a dazzling copper finish that adorns the front and rear bumpers, wrap-around trim, wheels, and engine components, which are easy to see since the car's hoodless. The copper-plated Cadillac's 5.9-liter Cummins is said to make up to 1,000 horsepower and 2,000 pound-feet of torque. 

Commissioned by Wet Sounds Marine Audio and built by Hot Rod Restos, this build was showcased during the SEMA show in 2016. It's hard to believe that was 10 years ago, and we'd venture to say that this build is still just as impressive a decade later. As wild as this thing it is, it most certainly isn't the only Cummins-swapped Cadi we've come across. Other notable swaps include a Cadillac dually limo as well as a turbo-diesel De Ville.

If you have a Rolls-Royce Phantom with an non-running naturally aspirated 6.7-liter V12, you could simply rebuild or replace the engine with factory parts. Alternatively, you could live large like YouTuber Westen Champlin, swap in a 24-valve Cummins turbo-diesel inline-six , and refer to it endearingly as a "Coals-Royce." 

Although a donor 5.9-liter Cummins was used for mock-ups, it was eventually upgraded to a 6.7-liter, courtesy of the fellas at Power Driven Diesel. As a result, the Phantom went from a 453-horsepower V12 to a coal-rolling turbo-diesel capable of making 1,500 horsepower. 

In addition to its bespoke engine swap, this Phantom also features an AirLift Performance suspension. The upgrade proved to be worthwhile during the first drive when Westen and company noted the Phantom's incredibly plush ride, and that was despite damage to the passenger side of the front subframe. The cabin of the Rolls has also maintained its serene nature, at least when the windows are rolled up. After seeing how comfortable it is, Westen noted his desire to take it on a cross-country road trip. We'd be lying if we said we don't want to experience this ourselves, and we'd be more than happy to settle for a short spin.

That's right, this is a boat with a 12-valve Cummins out back. How's that for wild? Given that this build was featured on Finnegan's Garage, which is hosted by the well-known Mike Finnegan from "Roadkill," chances are you've seen or at least heard of his turbo-diesel Tarva boat. 

No, the Cummins isn't quite as ludicrous as the 11.7-liter twin-turbocharged big block V8 powering Mike's boat, but it still offers more than enough power for a river rider. It represents the ambitions of a Cummins mechanic with a decade of experience who, after a few trials and tribulations, managed to work out gear ratios that optimized the diesel engine's rev range. 

As for the boat itself, the owner explains that it's a 1979 model that originally had a blown Ford 460 big block V8 that he swapped out for the aforementioned 5.9-liter Cummins, which was pulled from a 1997 Dodge pickup truck, along with a four-speed 47RE transmission outfitted with a manual valve body. The original motor was certainly cool, but a boat that can roll coal on the river is exceptionally wild.