This generation of the Thunderbird was restyled in favor of a more squared-off, “formal” look.
For 1966, the 390-cubic-inch V8’s power was increased to 315 hp (235 kW). The larger 428-cubic-inch (7.0 L) V-8 became optional, rated at 345 hp (257 kW) and providing a notable improvement in 0-60 mph acceleration to about 9 seconds. All models featured a new front clip. A flatter hood, re-shaped front fenders, new headlight buckets, new egg crate grille with large Thunderbird emblem, new bumper guards, a single bumper bar, and painted roll pan replaced the previous two model year’s two-piece front bumper. The rear taillights were revised, now a 3 piece unit going the full width across the rear, the backup light now located in the center section replaced the formerly rear roll pan mounted lamps.