Several national prep records are expected to be challenged at the 13th Arcadia Invitational track meet Saturday at Arcadia High. The best hope for a record is in the meet's final event, the boys' 1,600-meter relay. At the Pasadena Games on March 30, junior Obea Moore anchored Muir's relay to victory in 3:08.75, third-fastest ever. Muir will be pressed by Sterling High of Houston, which recently ran a 3:14.7 without being pressed. The record is 3:07.40 set by Hawthorne in 1985. Another potential record-setting event is the boys' 800 with Michael Granville of Bell Gardens facing Moore. Granville won the 800 at last year's meet in 1:47.96, half a second shy of the record. Field events begin at 5 p.m. and running events at 6. . . . Granville, a heavily recruited senior with a 4.0 grade-point average, signed a letter of intent with UCLA on Wednesday. He also considered USC and Arkansas. "UCLA pulled out all of the stops," he said. . . . Distance standout Michael Stember of Sacramento Jesuit is nursing a knee injury and will not run at the Arcadia Invitational. Stember is the defending state champion in the 1,600 and figures to have a good chance at becoming the first high school athlete to break a four-minute mile since 1967. He recently announced he will attend Stanford this fall. . . . Bryan Harrison, who won the 200 at the state meet last year while attending Dana Hills, is now a student at Rosewell High in Atlanta. He will run the 100 and 200 at Arcadia. . . . In his first season of competition, Gardena sophomore Quincy Brown is quickly making a name for himself. In a triangular meet last week, Brown went 6-6 in the high jump. "I just pulled this kid from the hallway, and he's a natural," Coach Keith Morris said. "That was his first meet high jumping, and look at the results." . . . Dorsey's Clarence Scott improved his national-leading high school mark in the long jump this season to 25-4 1/2 at the Oakland Invitational last Saturday. . . . The Van Nuys Birmingham boys' team won its 69th consecutive dual meet last Wednesday with a 68-59 victory over Woodland Hills Taft.