Pitching to a car buying market that no longer uses size as its only criterion for high class. Ford Motor Co. today introduced its slimmed down luxury cars that can achieve gas mileage better than three fourths of the cars now on the road.

Ford cut 600 to 1,000 pounds off its 1980 luxury models, although the cars look very much like the 1979 versions.And preliminary results from the government indicate the new cars will get a minimum of 16 mpg on the federal city test, compared to 12 mpg last year, Ford officials said today.

William O. Bourke, Ford executive vice president for North American automotive operations, said 1980 Continentals and Versailles will give "better gasoline mileage than three fourths of all the cars on the road today" in the United States. That includes about 110 million vehicles from aging VW Beetles through Mercedes diesels and all of last year's Ford products, if given the same federal government mileage testing, Ford executives said.

Other Ford people said that the 75 percent figure was intentionally conservative and, in fact, might even be higher.

Bourke said the United States is "hopefully coming back to reality today." He said there is a "recession of sorts" but is is mostly an automobile recession from the second quarter, and sales probably hit bottom two months ago.

Sales of 1980 models will run at a rate of close to 11 million units by the end of the year and increase from there because the recession will be both short and shallow. He contrasted that with the estimate for the 1979 model year of about 10.7 million units sold. All the fundamentals of the economy, from total employment through business inventories, now range from good to better, Bourke pointed out.

Most of the second quarter recession Bourke credited to slumping auto sales, with a bit of help from the housing industry. The recession was "artificially" stimulated by gasoline scares," Bourke said.

The executive laid much of the blame for the gasoline problems at the foot of the federal government. He said when anyone tries to allocate gasoline to states based on three-year-old consumption numbers, "the only thing you can predict is that you'll be wrong."

Bourke said projected imported car sales will be about 20 percent in the 1980 model year, down from the current year, and he predicted they will decline even more in 1981.

Ford, keeping with tradition by not announcing 1980 prices, did say that price increases with the official introduction of its models Oct. 12 will fall within the president's 7 percent guidelines.