In the past, you must have seen some incredible builds based on the 1970 Ford Boss 329 Mustang. But this one, with a 625-horsepower Chevrolet LS3 motor under the hood, is nothing short of a masterpiece. It's sure to raise many eyebrows thanks to its unique engine choice. However, a closer look would tell you that it packs a lot of potential and is one of the most outrageous builds you'll ever see.

Chris Ashton, the man behind this amazing creation, calls it the Ruffian Mustang and built it in his two-car garage. Though it was his first restomod project, it instantly became an internet legend due to its unique configuration. Nicole Johnson, the American professional monster truck driver, checks out this unique build in a video on her YouTube channel, Nicole Johnson's Detour.

Related: This Twin-Turbocharged V8 Powered Stealth Beetle Is A Hot Hatch Killer

The Real Story Behind The Ruffian 'Boss 427' Mustang

Ashton tells Johnson in the video that he has been working on cars since a very young age. He bought his first car before he could learn how to drive and worked on it in his parent's backyard. Though he has been modding vehicles for a long time, the Ruffian Mustang was the first car he built from the ground up. What's even more interesting, Ashton didn't have any professional automotive background and taught himself everything.

In college, he wanted to take a course that would teach him how to design cars. However, there wasn't such a curriculum, and he enrolled for a degree in graphic design and illustration. This decision led him to become a computer game designer by profession, but his love for cars never ended.

Ruffian 1970 Ford Mustang Side Profile
Nicole Johnson's Detour YouTube

He built this Mustang in his 40s and got invited by Toyo Tires to showcase it at their booth at the SEMA show. From there on, the popularity of the car just exploded. It got so much attention that even a couple of celebrities have made an offer for it. Ashton might have built this car in his garage, but now he owns a fabulous Ruffian workshop with three employees. Though he is still working as a game designer, he plans to make more exciting cars like this Mustang and sell them.

This Chevy LS3 Powered Boss Mustang Is An Autocross Champion

Ruffian 1970 Ford Mustang Front Three Quarters
Nicole Johnson's Detour YouTube

As Ashton says in the video, he was always into muscle cars. So his aim when building this Mustang was to create a Trans Am vehicle that he could also drive on the street. Part of this process was to keep the car as analog as possible, with little to no electronic trickery. And hence, the LS3 under its hood uses a carburetted setup instead of fuel injection since going for the latter would have taken away the original Trans Am experience.

Over the years, Ashton has participated in many autocross events, and he built this Boss Mustang for that purpose only. And, as he explains in the video to Johnson, it's set up not for the track but for low-speed grip and fast steering inputs.

Ruffian 1970 Ford Mustang Engine Bay
Nicole Johnson's Detour YouTube

His choice to go for the LS3 motor might be unconventional in the eyes of Ford purists, but as he explains, it helps a lot in autocross events thanks to its bucket-loads of torque. Another reason Ashton picked this Chevy crate engine is that he wanted something that would make the Mustang as fast as possible for the minimum upfront costs.

The aluminum block of the LS3 also helped keep the front of the car light, as Ashton didn't want the weight of a big-block motor on its nose. The Mustang uses a T56 Super Magnum 6-speed manual transmission from a Camaro SS, and the power goes to the rear wheels through a Torsen differential.

Related: Hot Off The Press: A Chevy Camaro Restomod Concept Just In Time For Christmas

This 1970 Boss Mustang Looks Cool, But It's Built For Functionality

Ruffian 1970 Ford Mustang Rear Profile
Nicole Johnson's Detour YouTube

All the exciting bits you see on this Mustang, such as the large fender flares, the chin spoiler, and massive air vents, are not there just to make the car look fantastic. Instead, they are critical to the car's performance. The huge fender flares allow for bigger tires, leading to more grip in the tight corners of an autocross track. The spoiler and the air vents help improve the Mustang's aerodynamics.

Apart from these, Ashton has also done a bunch of other interesting modifications that make this Mustang quite capable. For example, he used an old Trans Am trick to bend the nose of the car slightly by cutting out pie section pieces from its fenders to improve its aerodynamics further. He also went for the neat antic known as the 'Shelby Drop,' where he lowered the control arms by an inch, allowing for more negative camber in the corners.

Ruffian 1970 Ford Mustang Interior
Nicole Johnson's Detour YouTube

This 1970 Boss Mustang also gets a roll cage, racing seats, and, comically, a dodge-inspired stick shift lever. In its racing setup, it uses Hoosier slicks on all four corners wrapped around 11-inch rims at the front and 13-inch rims at the back. Stopping power comes from Wilwood brakes all around.

Johnson says that she is pretty intimidated by this Boss Mustang. However, this doesn't stop her from taking it out on an autocross track and having a blast.

Source: Nicole Johnson's Detour - YouTube