The curb weight I found for the 2014 Challenger w/V8 is 4160 lbs. I'm surprised it isn't more.
The 1967 Camaro weighed 2920 lbs (V8), the 2015 Camaro SS weighs 3900 lbs, for a gain of 1,000 lbs! Of course the '67 didn't have all the safety equipment, or creature comforts, or a stiff chassis, or decent brakes, etc. I'm not saying the new cars aren't better (they are), but they sure are a lot heavier.