Ford Authority

Ford Mustang Shelby GT350 Gets A Barra Inline-Six Cylinder Swap: Video

There’s no doubt that the current Ford Mustang Shelby GT350 has one of the most glorious engines ever produced – the high-revving, sweet sounding Ford 5.2L Voodoo V8. But when one guy’s GT350 burned to the ground during a track day a while back after the oil filter came loose, he was left with a decision – pay big bucks for a replacement, or dare to be different and swap in something completely different.

Ultimately, he went with option two, which turned out to be a turbocharged, 4.0L Ford Barra inline-six cylinder that saw duty in Australia’s Ford Falcon and Territory. This unconventional choice is unique enough on its own accord, but this might also be the very first engine-swapped current-gen Ford Mustang Shelby GT350 on the planet, too.

In stock form, these engines produced anywhere from 322 to 436 horsepower, but of course, this engine isn’t stock. This particular mill is of the FG variety, which means it has a better flowing head and is rear sump, which makes it ideal for this application. But thanks to a round of modifications and some tuning, the car laid down an astounding 870 horsepower and 700 pound-feet of torque on the dyno.

As if the engine of choice wasn’t strange enough for this Ford Mustang Shelby GT350, it’s also mated to an automatic transmission, something the Shelby isn’t available with from Ford. Regardless, that only helps this car’s brutal acceleration, as the owner finds out in this video. In fact, he describes it as “terrifyingly fast” at one point.

While the world remains strangely fascinated with swapping GM motors into Fords, it’s nice to see an unorthodox swap that keeps a car 100% Blue Oval. And we can’t wait to see how this car ultimately turns out, once they work all the bugs out of it.

We’ll have more cool videos to share soon, so be sure to subscribe to Ford Authority for more Ford Mustang news, Mustang Shelby GT350 news, and around-the-clock Ford news coverage.

Brett's lost track of all the Fords he's owned over the years and how much he's spent modifying them, but his current money pits include an S550 Mustang and 13th gen F-150.

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  1. Mark L Bedel

    That’s a lot of power and torque from a 4.0! I wonder how this power plant affected the front weight distribution? Better handling for the track?

  2. Noel Driver

    I definitely want to see a follow-up after they get that beast 100% dialed in. He seems to believe the chassis can handle even more power. Find the chassis’ sweet spot and let ‘er rip!

  3. John

    When I read “Barra,” I was expecting a GM engine!

  4. Blake Krause

    I like seeing more ‘traditional’ media sources surfacing content from YouTubers but no mention of Adam’s name? No credit on his photos? No mention of his channel? You’re making a guy that has been doing car builds for years with an automotive focused channel seem like some random guy that did this as a one off project

  5. fpvfan

    So this confirms that the the Barra I-6 will fit in the S550 chassis which means it is an option FORD SHOULD BE LOOKING AT TO PUT IN THE NEXT GEN S650 MUSTANG and CD6 PLATFORM VEHICLES. I’m sure that upgraded with modern Ecoboost Technology. a 4.0L Barra Twin Turbo I-6 engine could easily put out 485-495hp stock and over 500lb-ft of torque. Placing that above the standard high output 450hp 3.5L Ecoboost V6 and over the 400hp 3.0L Ecoboost and the 350hp 2.3L Ecoboost, and under the 660hp 3.5L Supercar spec Ecoboost V6 and the hybrid 494hp/630tq 3.0L Hybrid Ecoboost, Ford Could easily replace the dated 5.0L V8 and 5.2L V8 engine family all together. Actually the Barra 325T varriant had a rating of 436hp/425tq with the technology of the time back in the 2015-2016 Time frame. I’m sure ford is more than capable of massaging 445hp/480tq out of that to put in under a 485hp High Output variant, which would leave the Supercar 3.5L spec 660hp/550tq variant and a massaged 3.0L Hybird Ecoboost variant producing 520hp/585tq as the top two powertrains of the new CD6 platform performance vehicles, letting the 400hp/415tq 3.0 Ecoboost V6, a 350hp/400tq 2.7L Ecoboost V6 and a 330hp/495tq 2.3L Hybrid at the lower end of the spectrum.
    The Barra engines should power the new Mustang coupe/vert, Mustang 4-door coupe, mustang gasoline crossover and the Explorer GT and RS variants. The 660hp 3.5L ecoboost should be put in the Mustang and a new F150 Lightning and the 450hp 3.5L ecoboost should be the only powertrain option for the rest of the trucks besides the 3.0L diesel and the new Hybrid powertrain. This also includes the Expedition. The Ranger and Bronco should receive the 3.0L Ecoboost and the 2.3L Hybrid and 3.0L Diesel. The Super Duty should drop its name and become the Altas 250, Atlas 350, Atlas 450, etc and become fully electric to fight with the new Hummer pickup. Lincoln should drop completely and have the Vignale package to compete with the GMC Denali package. The Transit and all commercial vehicles should be electric, the Mach E needs a high performance model with the Cobra Jet 1400 E powertrain set up for the street. Bring back the C-Max and Make it better and that’s really it. The Maverick should be on the CD6 platform and get every engine listed above for the Mustang family and Explorer. Perfect lineup

  6. Melbourne351C

    Australian rev heads have known for years the Barra performance capacity is off the charts. Easy 1000BHP on a standard bottom end. Barra motors are cheap, pick one up at a yard for $300AUD. If you Google ‘Summernats 33 horsepower heroes’ you’ll see an aussie Ford Falcon pull 2200 rear wheel horses out of a 4lt straight 6 daily driver. That’s [email protected] quarter mile despite a curb weight of 4180lb. Good to see America waking up to Aussie engineering. Shame Ford Australia gave up on us.

    BTW: It’s Barramundi(Aussie Fish) NOT Barracuda

  7. Rodger dodger

    1000bhp on stock Bottom end is way off the mark

    Stock block yes but bottom end No, it will need rods and pistons and Oil pump gears if you like rpm as a minimum. Granted they don’t take much to boost up but money needs to be spent

    Also there are multiple different Barra bottom ends, varying rod strengths and compression ratios, cam profiles and injectors – 300$ will buy you a 400bhp grenade with high mileage if that’s what you want. The Better stock pickings will do high 600rwhp on e85 and a reasonable tune


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