The Ford Mustang is set to go hybrid according to reports from the US, as emissions regulations threaten the legendary sports car’s future. According to Ford Authority, a hybrid version of the current S650 generation Mustang is in the works, codenamed ‘S650E’, with prototypes having reached the ‘prove-out stage’. Ford Australia introduced a plug-in hybrid (PHEV) version of its best-selling Ranger dual-cab ute earlier this year, using the same 2.3-litre turbocharged four-cylinder found in the Mustang EcoBoost. A previous plan to introduce a hybrid Mustang to showrooms back in 2020, following a significant $US700 million ($A1.06 billion) investment in the Flat Rock Michigan plant, was shelved. MORE: Ford planning 1000hp off-road ‘supercar for gravel’ MORE: Explore the Ford Mustang showroom