Does anyone know the approximate weight of the 1983 Z28?

3200 pounds, give or take.

Over on the thirdgen.org site, they are quoting 3500+ because of all the electronics-door locks, power windows, A/C system, and all the other requisite items that came on a fully loaded car.

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1969 Camaro SS 350-383ci., T-56, 12 bolt, Eaton posi, 3.31 gears, 4 wheel disc, Deluxe black houndstooth interior, rear window defogger, tilt steering, console w/AutoMeter gauge package, center mntd. clock, Tach.

According to GM the curb weight on a 1983 Z28 is 3160 pounds.