  We present computations for the accretion disk limit cycle model in an
attempt to explain the empirical relation for dwarf nova outbursts between the
peak visual absolute magnitude and orbital period found by Warner. For longer
period systems one sees intrinsically brighter outbursts. This is accounted for
in the limit cycle model by the scaling with radius of the critical surface
density $\Sigma_{max}$ which triggers the dwarf nova outbursts. During the
storage phase of the instability the accretion disk mass must be less than some
maximum value, a value which scales with radius and therefore orbital period.
When the instability is triggered and the accumulated mass is redistributed
into a quasi steady state disk in outburst, the resultant peak optical flux
from the disk is a measure of the total mass which was stored in quiescence. We
compute light curves for a range in outer disk radius (or equivalently, orbital
period), and find that our peak values of $M_V$ are within $<1$ mag of the
observed relation $M_V$(peak)$=5.64-0.259P_{orbital}$(h) for $2\la
P_{orbital}$(h)$ \la 8$.
