For quite some time, muscle car fans on the internet have been perplexed by the very Mustang seen here. The unusually large hood bulge caused a stir, with some speculating it was a test mule for an even more powerful Mustang Shelby GT350. Others assumed a new Cobra Jet - the company's incredible turn-key dragster - was on the way.

But Ford has finally let the cat out of the bag, inviting Ford fan and YouTuber REVan Evan to get an exclusive first look at what lurks beneath the prominent bulge. So, what is under the hood? None other than Ford Performance's new 7.3-liter Godzilla V8 mated to a manual gearbox.

"This is our test bed for our 7.3-liter manual transmission control pack and crate engine combination," explains the subsidiary's Mark Wilson. "This is designed to fit in any vehicle. It's a complete standalone engine management system. You could put it in a '56 Ford, a '69 Mustang, or you could put it in a 2020 GT350 if you want."

Amusingly, there was no real motive behind using a GT350 as a test mule. "We chose this vehicle because quite honestly, [it was just] laying around," adds Wilson. When asked how the engine squeezes under the Mustang's hood, he explains that it fits easily, save for one rather obvious issue.

"There's a hood clearance issue," notes Wilson. Aside from that, he notes the new crate engine bolts right in and has plenty of clearance on either side. "It's a compact engine that can fit in nearly any application." Out on the road, the 7.3-liter V8 emits a mighty bellow, punctuated by the wonderful sound of a manual gear change.

Ford Performance engineer Dave Born explains the packaging issue will be a thing of the past, as a new intake manifold is on the way. "It's going to look a lot like a production manifold, we've made some changes ... you've got this upswept throttle neck. It's not very package-friendly." Ford Performance has created a new manifold with a more traditional design.

"Beyond that, the runner pack is a little bit shorter, so it's going to move the rpm peak up a little bit, but keep that great torque that we get with the base manifold," explains Born. Elsewhere, the throttle flange has been upsized to work with the GT500's throttle.

If you've got an engineless project car stashed away in the garage, you're probably salivating right now. Thankfully, you shouldn't have to wait long to get your hands on the 7.3-liter motor with the manual transmission. Wilson said customers can expect an introduction in the fourth quarter.

Thankfully, would-be buyers won't have to contend with the bizarre bulging hood seen on this unique Mustang Ford has already developed a prototype manifold that will make for a neater installation and a more streamlined look. "It's designed for street use," noted Wilson. "[For racing], you might be better off with an aftermarket intake."

The biggest changes include a revised inlet, but Ford has also redesigned it to accommodate an engine cover. While there's no official pricing as yet, Wilson is confident the package will be competitively priced. It's worth noting that Ford Performance does currently offer a 7.3-liter pushrod V8 with the 10R140 automatic transmission.

Priced at $19,995, we anticipate the manual variant will weigh in at a similar price point. Even though Ford is preparing to tackle the electric era with all its might, it's heart-warming to see Dearborn is still catering to the enthusiast's needs. The new Mustang will be revealed in less than a month and is expected to retain ICE engines for many years to come.

Of course, it's only a matter of time before the all-electric Mustang arrives. Rumors suggest the battery-powered pony car will arrive in 2028 but, for now, we can all revel in the sonorous sound of a V8 engine.