A scroll type fluid displacement apparatus including a housing and a pair of scrolls having interfitting spiral wraps which undergo relative orbital motion to make moving line contacts and define sealed off moving fluid pockets of changing volume. The center portion of at least one of the wraps is higher than the remaining portion thereof. The center portion extends substantially from the inner end of the spiral wrap outwardly at least to the location of the line contact between the curved surfaces of the wraps when the innermost pair of fluid pockets are merged into a single fluid pocket to form the high pressure space near the center of the scrolls. This construction prevents abnormal wear of the spiral wrap and the opposite end plate which might otherwise occur during axial slant of the orbiting scroll, or which might be caused by non-parallelism of the scroll end plates, without compromising the important sealing of the central high pressure space.