My 63 Polara hardtop was a touch under 3400# with a 440 and a PB automatic.
Basically a stock car with a bench seat, steel wheels w/ poverty caps, and a spare in trunk.
Only weight related mods were an alum intake, headers, and radio delete, so a few lbs off there, but not much.
Car was from Cali, so it had no undercoating and such. Oh, and it was 4 wheel drum brakes
My buddy and I weighed our cars at the same time and his 70 camaro with a small block weighed 50# more than mine, would have never guessed that.