Does a 1980 z28 camero have posi-track rear end?

No, a 1980 Z28 Camaro did not have Posi-Traction (or Positraction) as standard equipment. While it was a *available* option, it wasn't included in every Z28. Many came with a standard open differential. To know for sure if a specific 1980 Z28 has Posi-Traction, you'd need to check the original documentation (build sheet or dealer invoice) or inspect the rear differential itself.