


With the same power as the larger Buicks and less weight, the Riviera had sparkling all-around performance: Motor Trend magazine found it capable of running 0-60 mph (0-96 km/h) in 8 seconds or less, the standing quarter mile in about 16 seconds, and an observed top speed of 115mph...and faster in a longer stretch of road.
The
Riviera underwent a major restyle in 1966, the start of the second
generation. The headlights were moved back in the grille, and retracted
above the grille when not in use. The vent windows were eliminated and the
roof and rear deck gained fastback like styling. The hood became longer,
reported the longest ever on a car, and the taillights were redesigned. The
Buick Riviera GS lost its two carb option (though 198 copies were dealer installed), and
the 401 engine was dropped, so the 425 cid 340 bhp became the only factory
engine choice. The restyle was a hit with customers and 45,348 copies were
sold, a 50% increase over the year before.