The Ford Mustang Convertible was one of two body styles (alongside the Hardtop) that were introduced when the Ford Mustang was first launched as an unofficial 1964-1/2 model. These "1964-1/2" Mustangs were available with a "U-code" 170 cubic inch (2.8L) inline six, an "F-code" 260 cubic inch (4.3L) V8, or the "D-code" 289 cubic inch (4.7L) four-barrel carburetor V8 (210hp). Upon the 1965 Mustang's official introduction (built after August 1964, and referred to as "late 1965s"), these engines were replaced by the "T-code" 200 cubic inch (3.3L) inline six, the "C-code" 289 cubic inch (4.7L) two-barrel carburetor V8, the "A-code" 289 cubic inch (4.7L) four-barrel carburetor V8, and the top of the line "K-code" 289 cubic inch (4.7L) HiPo (High Performance) V8. Depending on the engine used, these Convertibles were available with a 3 speed manual, a 4 speed manual, or a 3 speed automatic transmission, all of which sent drive to the rear wheels. For the 1967 model year, Ford updated the Mustang, which resulted in the 1967-1968 First Generation Ford Mustang.