The Ford Tempo and its Mercury counterpart the Topaz, are compact cars produced by the Ford Motor Company for model years 1984 to 1994. They were the downsized successors to the Ford Fairmont and Mercury Zephyr respectively. The Tempo and Topaz were the second in a series of aerodynamically-styled cars from Ford, preceded by the 1983 Ford Thunderbird and followed by the first generation Ford Taurus. Although Ford tried to portray the Ford Contour and Mercury Mystique that arrived in 1995 as new, up-market models, they are generally seen as the successors of the Tempo and Topaz. Development In the late 1970s Ford began planning to replace their compact rear wheel drive Ford Fairmont and Mercury Zephyr models with a new smaller front wheel drive (FWD) car. This new compact was expected to compete in the marketplace with General Motors' X-Body, but wound up more similar to GM's J-cars. Ford's chief development engineer for the new car was Ed Cascardo. The Tempo and Topaz chassis shared some parts with the front-wheel-drive platform used on the first North American Ford Escort, but with a wheelbase stretched by and distinctive new bodies. There were few common components due to the Tempo and Topaz's larger size. Switching to front-wheel drive freed up interior space that would have otherwise been lost to accommodate a driveshaft and rear differential. Wind tunnel testing on the Tempo began in December 1978. More than 450 hours of testing resulted in over 950 different design changes. The Tempo and Topaz both featured windshields inclined at a 60° angle and aircraft-inspired door frames, two features that had both appeared on the Thunderbird and Cougar in 1983. The door frames wrapped up into the roofline, which improved sealing, allowed for hidden drip rails, and cleaned up the A-pillar area of the car. The rear track was widened, improving aerodynamic efficiency. The front grille was laid back and the leading edge of the hood was tuned for aerodynamic cleanliness. The wheels were pushed out to the corners of the body, reducing turbulence. The cars' backlights were also laid down at 60°, and the rear deck was raised, reducing drag and resulting in greater fuel efficiency. Viewed from the side, the raised trunk imparted a wedge stance to the car which was especially prominent on the two-door coupes. The aerodynamic work resulted in a coefficient of drag () of 0.36 for the two-door