Gladney Brothers 5.0 Boss Is an Ultra-Rare Motorsports-Inspired Fox Body Mustang
One of just nine built in total, this Gladney Brothers Boss 5.0 has a completely new Mach 1-inspired body and plenty of power under its hood.
Throughout the course of history, there have been many rare and special Ford Mustang models, many of which are quite valuable – with price tags reaching the million-dollar mark in some cases. However, there are also some very obscure Mustang-based builds that have emerged from various shops over the same time period, many of which either failed to find a foothold in the market or were simply victims of the fact that building and selling custom vehicles isn’t an easy business to break into. The car you’re looking at here – the Gladney Brothers 5.0 Boss – is such a machine, and its history is, well a bit of a mystery.
Recently, the FoxBodyFX YouTube channel got the chance to check out a very special Gladney Brothers 5.0 Boss up close, which is especially notable because only nine were ever built. It was put together back in 2000 as a road-going version of that same outfit’s GB400R racer, which won the SCCA Super Production Championship in 2001, though some internal issues led to an impromptu retirement before it could try and repeat that feat in 2002.
To create the Boss 5.0 roadster, GB took a regular old Mustang convertible and gave it an entirely new look with fiberglass body parts, all with one goal in mind – to make it look more like the 1969 Mach 1 than a modern Fox. During that process, they ditched the rear seat in favor of a tonneau cover with hoops to protect the occupants in the event of a rollover, though the car does have a two-piece hardtop that can be installed in the event inclement weather pops up.
Other than its unique looks, the Gladney Brothers Boss 5.0 truly shines in terms of performance as well, thanks to a series of upgrades. The biggest is its punched-out 306 cubic-inch V8, which generates around 375 horsepower – a very strong number for its time. GB also addressed handling by giving the car a full suspension makeover and beefier brakes to boot.
Today, the Gladney Brothers Boss 5.0 roadster lives on as an incredibly rare and somewhat obscure piece of pony car history, one that’s quite honestly more unique than most other third-party builds that preceded it. After all, how many can claim that they exist not only as a rebodied Mustang, but also a car that was directly inspired and built by a motorsports outfit?
Join the Mustang Source Forums now!
You must be logged in to post a comment.