Combining resolved optical spectroscopy with panoramic HST imaging, we study the dynamical properties of spiral galaxies as a function of position across two intermediate-redshift clusters, and we compare the cluster population to field galaxies in the same redshift range. By modeling the observed rotation curves, we derive maximal rotation velocities for 40 cluster spirals and 37 field spirals, yielding one of the largest matched samples of cluster and field spirals at intermediate redshift. We construct the Tully-Fisher (TF) relation in both V and Ks bands, and find that the cluster Tully-Fisher relation exhibits significantly higher scatter than the field relation, in both V and Ks bands.