Chrysler Corp. yesterday reported second-quarter earnings of $310.3 million, marking the best quarterly performance in the company's 58-year history.

The 1983 second-quarter results, yielding $2.41 per share, represent a 190 percent gain over the $106.9 million ($1.34 a share) earned in the same period last year.

Warner Communications Inc., on the other hand, stunned Wall Street by posting a $238.4 million second-quarter loss ($4.38), attributable mainly to a mammoth and unexpected $310.5 million operating loss by Atari Inc., its troubled videogames and personal computer company.

The company's six-month loss totaled $302.2 million ($4.69), compared to a profit of $146 million ($2.25) in the first half of 1982. "A loss of this magnitude clearly was not anticipated," said Warner Chairman Steven J. Ross in a prepared statement.

Atari's operating loss through the first half of this year totaled $356 million compared with a year-earlier operating profit of $212.4 million.$.

The announcement of Chrysler's record profits came one day before United Auto Workers union leaders were scheduled to meet in Detroit to consider reopening their contract with the once-struggling automaker.

Under the current UAW-Chrysler agreement, which expires Jan. 14, 1984, Chrysler production workers get about $2.12 less in hourly wages than their counterparts at General Motors Corp. and Ford Motor Co.

The difference is largely the result of nearly $1.068 billion given up by Chrysler workers since 1979 in what became a successful campaign to help the company avoid bankruptcy. Chrysler union officials say they do not expect to gain parity with their GM and Ford locals by the end of this year, but they do expect a renegotiated contract to provide wages "substantially higher" than those now paid to Chrysler employes.

Chrysler earned $482.4 ($4.72) in the first six months of 1983, compared with $256.8 million ($3.29) in the same period last year. The 1982 earnings included a one-time, $239 million gain from the sale of Chrysler Defense Inc. to General Dynamics Corp.

The company's share of the domestic passenger car market was 10.6 percent in the first six months of 1983, up from 9.9 percent in the year-ago period.