  We present numerical calculations of the production cross section of a heavy
Z' resonance in hadron-hadron collisions with subsequent decay into top-antitop
pairs. In particular, we consider the leptophobic topcolor Z' discussed under
Model IV of hep-ph/9911288 which has predicted cross sections large enough to
be experimentally accessible at the Fermilab Tevatron and the Large Hadron
Collider at CERN. This article presents an updated calculation valid for the
Tevatron and all proposed LHC collision energies. Cross sections are presented
for various Z' widths, in p-pbar collisions at \sqrt{s}=2 TeV, and in p-p
collisions at \sqrt{s}=7, 8, 10 and 14 TeV.
