Here is how my 04 Coupe scaled out at last year before major modifications. Disclaimer here is that it was riding on SRT6 springs and had SRT6 brakes. The rest of the car was fairly close to stock, as far as weights go. The brakes would not materially change the way it scaled (perhaps by a few pounds at each corner for the bigger rotors). If I was to guess, probably 20# total for the car. Springs could change the corner weights, but not materially change the overall weight of the car. One of these days we'll put one of the dead stock cars onto the scales.