Mitsubishi Motors Corp. is set to halt production of two unpopular sports-car models , the Nikkei Industrial Daily reported Wednesday. The car maker's consideration to drop the GTO and FTO sports cars from its lineup is part of its plan to slash costs by cutting the number of models it offers. The decision is also prompted by the likelihood that the two models will not meet new, stricter side-impact regulations set to go into effect in September 2000.