I have a 92 RS w/ 305 TBI. The acceleration is awful especially at high speeds! Torque seems to be fine. Sometimes the car will misfire when I start it.(check engine light will come on after it happens, then goes off once I restart the car) It seems like the RPMS don't get high because the motor is pretty quiet when I damn near floor it( Tachometer is messed up, the needle stays on the opposite end of the meter so I never know the RPMS) I have a 92 caprice with the same 305 and it needs a tune up bad but still accelerates faster than my camaro and I can actually hear the motor revving how it's supposed to. When I go over 50mph (in the camaro)it takes 30+ feet to gain 5mph. I have no clue what it can be. I know about cars but not as much as you guys so if it's something complicated please explain it to me or I'll just be lost haha! Thanks

Just one of the reasons is it most likely still has the 2.73 gear ratio. The 5.0 is not exactly a performance engine but with those 2.73 rear end gears its a complete dog.
Drop in a 3.42 rear end gear ratio and L.S.D., aka = Posi and it will wake it up some.
Check the base timing. If its at "0" its set to stock and could benefit from a small amount of timing advance. Say just 2* or 3*.

It's already posi rear end