An article by J. J. Pignatiello, Jr. and J. S. Ramberg in the Journal of Quality Technology (Vol. 17, 1985, pp. 198- 206) describes the use of a replicated fractional factorial to investigate the effect of five factors on the free height of leaf springs used in an automotive application. The factors are A = furnace temperature, B = heating time, C = transfer time, D = hold down time, and E = quench oil temperature. The data are shown in Table 14E.4.

The design and data are in the Minitab worksheet Ex14-9.MTW.
Enter the factor levels and response data into a Minitab worksheet, and then define the experiment using Stat > DOE > Factorial > Define Custom Factorial Design.

TABLE 14E.4 The Spring Experiment for Exercise 14.9 A B CDE --7.78. 7.78. 7.8 8.15, 8.I8 788 --+7 50 756. 750 +759. 756, 7.75 754. 8.00. 7.88 ++7.69, 8.9. 8.06 - 7.56, 7.52. 7.44 7.56, 7.81. 769 -+ 7.50, 7.25, 7.12 ++ 7.88, 7.887.44 --+750. 756. 750 7.63 7.75, 756 -+7.32 7.44. 7.44 +-+ 7.56, 769 7.62 ++7.18. 7.18. 7.25 +4+781. 750, 759 +-+8