We study the expansion properties of the contracting Lorenz flow introduced
by Rovella via thermodynamic formalism. Specifically, we prove the existence of
an equilibrium state for the natural potential ϕ^t(x,y,z):=−tlogJ(x,y,z)cu for the contracting Lorenz flow and for t in an interval
containing [0,1]. We also analyse the Lyapunov spectrum of the flow in terms
of the pressure