  Calculations of the spectra of various even-even nuclei in the fp shell
({44}Ti, {46}Ti, {48}Ti, {48}Cr and {50}Cr) are performed with two sets of
two-body interaction matrix elements. The first set consists of the matrix
elements of the FPD6 interaction. The second set has the same T=1 two-body
matrix elements as the FPD6 interaction, but all the T=0 two-body matrix
elements are set equal to zero (T0FPD6). Surprisingly, the T0FPD6 interaction
gives a semi-reasonable spectrum (or else this method would make no sense). A
consistent feature for even-even nuclei, e.g. {44,46,48}Ti and {48,50}Cr, is
that the reintroduction of T=0 matrix elements makes the spectrum look more
rotational than when the T=0 matrix elements are set equal to zero. A common
characteristic of the results is that, for high spin states, the excitation
energies are too high for the full FPD6 interaction and too low for T0FPD6, as
compared with experiment. The odd-even nucleus {43}Ti and the odd-odd nucleus
{46}V are also discussed. For {43}Sc the T=0 matrix elements are responsible
for staggering of the high spin states. In general, but not always, the
inclusion of T=0 two-body matrix elements enhances the B(E2) rates.
