In the outstanding performance of his career, John Pringle swam a 4:24.5 for a second place in the 400-yard individual medley in the National Collegiate Athletic Association championships in Raleigh, N.C., yesterday. The Harvard swimming ace swam four full seconds faster than he ever had before to finish two seconds behind victor Ed Townsend of Yale.

In the afternoon, Pringle had placed sixth in the trial heats with a time of 4:31.9. John House of Southern California qualified first with a time of 4:23.5, but in the phenomenal final, House could only take third place behind Pringle and Townsend.

In the final, Pringle went into the last 100 a full body length ahead of Townsend, but he just could not stave off the strong freestyle finish of the Yale swimmer.

Pringle and Townsend finished the first 100 in a tie, but Pringle pushed a full body length ahead of Townsend in the breaststroke, and it looked like the race was won. Townsend, refusing to tire, however, came back in the freestyle. After catching Pringle, Townsend pulled relentlessly ahead to win by two body-lengths.

Dave Abramson, the only other Harvard swimmer in the meet, placed third in his heat of the 500-yard freestyle with a time of 5:13.0, but did not qualify for the finals. The race was won by John Konrad of Southern California in a time of 4:50.7.

In other events, Minnesota beat Yale in the 400-yard medley relay in a time of 3:35.2. Steve Jackman of Minnesota won the 50-yard freestyle in 21.2 seconds, and, for the second year in a row, Ohio State's Lou Vittucci took the diving title.