My Demon which is race only weighs in at 2500#. The only part that is still the original sheet metal is the quarters and roof. Over 3/4 of the firewall is aluminum and about 1/3 of the front floor pan is aluminum. The trunk area is all aluminum and under there are no inner fenders. The front end is race weight fiber glass, as well as the doors, deck lid and rear bumper. The only real glass are the tip out rear windows. I have no idea how it worked out the way it did, but with 5 gallons of fuel, the two batteries, me with a race suit and helmet on the scales it came out at 625# per corner with a 50/50 weight bias.