The Census Bureau yesterday, acting in the face of lawsuits by seven cities, ruled out any adjustment in its population figures for purposes of congressional reapportionment.

But it left open the possibility of recounts for allocating federal funds.

"The agency's decision not to adjust for apportionment [of congressional seats] is based on its understanding of constitutional law as well as census law as passed by Congress," Census director Vincent J. Barabba said at a news conference.

He said he based his position on Justice Department arguments presented in court as defense against a suit filed by Detroit.

Detroit is one of seven cities that have gone to court to force adjustment of the figures. The others are New York, Newark, Philadelphia, Baltimore, Chicago and Chester, Pa.

"The Bureau has determined that it should not, and in fact could not, adjust the data in a satisfactory manner in time to meet the statutory deadline for turning over the state totals to the president for reapportionment of the House [by] Dec. 31, 1980, nor could we accomplish this task by April 1, 1981, for use in state and local redistricting," Barabba said.

Many localities have expressed satisfaction with the census count, Barabba said, including San Diego, Los Angeles County, Sheby, Ohio, Portland, Maine, and Lowell, Mass.