An Irwin L. Jacobs-led investor group has raised its stake in Borg-Warner to 7.7%, or 6.66 million shares . . . A group of investors led by J. Hugh Roff Jr. said they acquired Petrounited Terminals Inc. from Midcon Corp., a wholly owned subsidiary of Occidental Petroleum, for undisclosed terms . . . Dart & Kraft announced that it has changed its name to Kraft Inc. . . . Pasadena-based Hershey Oil signed a letter of intent to buy Caland Petroleum Corp., Denver, in a transaction valued at about $2.4 million.