The Trans Ams have different horsepower ratings depending on the model year. Some exemples: 1993 to 95 cars had 275 hp. The 1996 to 97 TAs had 285 hp. These are the ones with the LT1 engine. The 1998 to 02 models with the LS1 engine, had 305 hp.
1 Additional Answer
The amount of horsepower that a Trans Am has depends on the vehicle and the engine. The models from 1993 to 95 has 275 hp. The 1996 ad 1997 models had 285 hp.