Can you have more than 6 pods?

We have a very large house (8,500 sq ft - 3 levels) and I recently installed 6 pods.  They seem to be working well, but could probably use a few more.  For whatever unknown reason - the cable line enters our house through the basement (not ideal) - which is where the gateway is located.  I'm trying to find out if there is a maximum number of pods that can be installed.  Thanks for the help!