Four-cylinder engines were gone. Base models got a V6 engine, while the GT held a 215-horsepower V8. Manual shift was standard; electronically controlled 4-speed automatic optional. All Mustangs now halted with all-disc brakes, with antilocking an option for the first time. Convertibles included a power top and glass rear window, with a rear defogger optional. Mustang Cobras with 240-horsepower V8s were sold only in limited quantity. Firmer suspended than ordinary Mustangs, Cobras came only with 5-speed manual shift and had all-disc antilock braking as well as a unique appearance.