ENGINE
The Demon 340’s LA-architecture V-8 displaced (wait for it) 340 cubic inches. For 1971, with 10.3:1 compression, it was advertised at 275 gross horsepower; for ’72, with compression dropped to 8.5:1, Demon 340 was rated at 240 net horsepower.
TRANSMISSION
A floor-shifted three-speed manual was standard but not common. The Hurst-shifted A-833 four-speed manual and A-727 TorqueFlite three-speed automatic were available as extra-cost options.
INTERIOR
Demon 340s shared the Duster 340’s sportier gauge cluster for 1971. A bench seat was standard (all-vinyl in ’71, vinyl-and-cloth in ’72) with a tach, bucket seats, console, and Tuff Wheel all optional.
CHASSIS
In 1971, the Hi-Performance Axle Group A31 was optional on the Demon 340 and included a heavy-duty 3.91 axle, Sure Grip differential, and the maximum cooling package. It wasn’t available…