  The predicted orbital-period distribution of the subdwarf-B (sdB) population
is bi-modal with a peak at short (< 10 days) and long (> 500 days) periods.
Observationally, many short-period sdB systems are known, but only few wide sdB
binaries have been studied in detail. Based on a long-term monitoring program
the wide sdB sample has been increased, finding an unexpected correlation
between the eccentricity and period. In this article we present the orbital
solution and spectral analysis of four new systems, BD-7.5977, EC11031-1348,
TYC2084-448-1 and TYC3871-835-1, and update the orbital solution of PG1104+243.
Using the whole sample of wide sdBs, we aim at finding possible correlations
between orbital and spectral properties, with as goal improving theoretical
models of Roche-lobe overflow. High-resolution spectra were obtained to
determine the radial velocities of both the sdB and MS components. Surface
gravities and temperatures of both component were derived from photometric
spectral-energy distributions. Spectral parameters of the cool companion were
verified using the GSSP code. Furthermore the amount of accreted mass was
estimated. Orbital parameters matching the earlier observed period-eccentricity
relation were found for three systems, while TYC 2084-448-1 is found to have a
lower eccentricity than expected from the period-eccentricity trend indicated
by the other systems. Based on new observations, the orbit of PG 1104+243 has a
small but significant eccentricity of 0.04 $\pm$ 0.02, matching other systems
with similar periods. Furthermore, a correlation between accreted mass and
orbital period was found, as well as a possible relation between the initial
mass-ratio and the final period-eccentricity. The wide sdB-binary sample shows
interesting possible correlations between orbital and spectral properties.
However, a larger sample is necessary to statistically validate them.
