Police were called to outside the Big John's takeaway in Cooks Lane, Kingstanding, just before 8.30pm on Saturday, April 11.
Two men had entered the premises to collect their food after parking their Audi A4 car – when they noticed a small blue Hyundai i10 car pull up alongside and then heard the engine of their Audi start.
The Audi car was driven off by a man through the car park and into a Esso petrol station nearby, when the car stalled and the victim and his friend had the opportunity to run after it and confront the driver.
The 35-year-old victim was then punched in the face by the thief and then reversed into by the thief's accomplice in the Hyundai car.
The victim did not sustain any serious injuries – and the two offender fled the scene and left the Audi behind.
DC Amrit Nepaul, from West Midlands Police's High Harm team, said: "I am asking people to cast their minds back and let us know if they noticed any suspicious behaviour in the area that day. Perhaps you saw the little blue Hyundai car driving off at speed or even witnessed what you thought was some kind of disorder.
“We are continuing to investigate any CCTV or forensic opportunities, but could really do with any information on the description of those involved or even any dash cam footage that could show us before or after the offence. If you know anything, please do not hesitate to get in touch.”
Anyone with information can call West Midlands Police on 101, quoting crime reference 20SH/87803P/20.