after 1980, other equipment was introduced and assigned to "tze-chiang" service, including emu200, emu300, e1000 push-pull, temu1000 tilting train on electrified lines, and dr2800, dr2900, and dr3000 on non-electrified lines. from 6 july 1991 through 31 march 1992, tra piloted business class service on selected departures. however, due to low ticket sales, the experiment was terminated. in 2010, tra redesignated certain former business class coaches (bck) on the "chu-kuang" express as "tzu-chiang".