The ornamental design for a portion of a tiretesting calibration device, as shown and described.
FIG. 1 is a perspective view of a portion of a tire testing calibration device showing the new design;
FIG. 2 is a top elevation view of one side of the portion of a tire testing calibration device as shown in FIG. 1;
FIG. 3 is a front elevation view of the portion of a tire testing calibration device shown in FIG. 1;
FIG. 4 is a side plan view of the portion of a tire testing calibration device shown in FIG. 1;
FIG. 5 is a back plan view of the portion of a tire testing calibration device shown in FIG. 1;
FIG. 6 is a side plan view of the portion of a tire testing calibration device shown in FIG. 1; and,
FIG. 7 is a bottom plan view of the portion of a tire testing calibration device shown in FIG. 1.
The broken lines showing the remainder of the tire testing calibration device are for illustration purposes only and form no part of the claimed design.