Prototype Mustang combines a custom wide-body and fastback roof with advanced suspension development for a unique high-performance build.
A one-of-a-kind 2005 Ford Mustang, built as a development prototype for Kenny Brown’s elite suspension systems, has emerged as a rare fusion of engineering precision and muscle car nostalgia.
Dubbed the Kenny Brown CSR-69, this custom Mustang was more than a showpiece—it was the official test platform for Brown’s Advanced Geometry Suspension System (AG-ST). That development pedigree makes it unique even among the brand’s limited production models.
At the heart of the car is a tuned 4.6-liter SOHC V8 producing over 350 horsepower, thanks to a custom ECU calibration, performance intake, and high-flow exhaust system. Paired with a performance clutch and short-throw shifter, it promises sharp response both on the street and the track.
What sets the CSR-69 even further apart is its fully custom, all-steel wide-body construction and a hand-fabricated fastback-style roofline, evoking the iconic 1969 Mustang. With added functional aero like a front splitter, sculpted side skirts, and a rear spoiler, the car wears its performance intentions on its sleeve.
Underneath, the car features prototype-level suspension components developed by Kenny Brown himself, including upgraded coilovers, sway bars, recalibrated steering geometry, and a reinforced chassis. It was tuned not only to showcase but to shape the future of the company’s suspension performance standards.
Inside, the CSR-69 continues the race-inspired theme with bolstered sport seats, carbon fiber accents, a custom gauge cluster, and Kenny Brown-branded trim elements. The result is a cockpit tailored for serious driving but refined enough for daily use.
Only one CSR-69 prototype like this exists. It’s individually certified by Kenny Brown Performance and represents a pivotal chapter in modern Mustang performance development, making it a highly desirable collector’s item.
