According to NetCarShow.com:
The original Aston Martin V8 Vantage was hailed at the time of its 1977 introduction as "Britain's Supercar" for its 170 mph (274 km/h) top speed. Its engine was shared with the Aston Martin Lagonda, but the Vantage used high-performance camshafts and bigger carburettors for increased output.
The Vantage name had previously been used on a number of high-performance versions of Aston Martin cars, but this was a separate model. Although based on the Aston Martin V8, numerous detail changes added up to a unique driving experience. One of the most noticeable features was the closed-off hood bulge rather than the open scoop found on the normal V8. The grille area was also closed off for Series I cars.
The Series II cars, introduced in 1978, featured an integrated spoiler and smoother lines in the body. One obvious exterior clue is the square turn signal lights on the front fenders between the wheel opening and the headlights. Inside, wood replaced some of the vinyl padding giving a more luxurious appearance. This line was produced, with some changes, through 1986.
The 1986 through 1989 Series III V8 Vantage was more of a mechanical update. 16 inch (406 mm) wheels were now fitted, as was the more powerful V8 from the limited-edition Aston Martin V8 Zagato. This car was changed somewhat for the United States market - it lacked the powerful Vantage engine but retained the Vantage name, and the look was changed with a flattened hood.
A Aston Martin V8 Vantage Volante convertible version was also produced.