lone,
i dont know what my car weighs, but it is probably as light as a 240z. My 280zx has everything either stripped put or things on the way out. my motor is just an l28 with su's. everything in the engine bay is gone. the interior is completly gone minus the door panels and the seats and the dash. the car is just basically a shell with seats and drivetrain.
the reason it is stripped and torn apart is that im redoing everything one part at a time. I have stripped a few hundred pounds from the zx.
now back to his 280zx. removing the ac will also make the apperance of the engine bay a bit more eye happy. I can also tell you when i removed the belt that drives the AC, before i removed the whole thing and the mounting plate under it, the engine would up lots faster.
Now mack, if you wanna remove the AC, you should just go ahead and remove the cooling fan and install electric fans if you havent already. this will drastically improve the revs on your motor. do you have power steering?