Try putting a wait - even 0 ms - inside your loops. Without a wait, LabVIEW attempts to run your loops as fast as possible, and in your case, this could be starving the operating system of the chance to send your data over the network connection.
Run a quick search on this forum for "Nagel algorithm." You may be able to speed up transfers by disabling it.
Why are you converting your data to an ASCII representation, then converting back again? Why does your reader only read one digit at a time? You will do better if you convert your data directly to a string (using flatten to string or typecast). On the receiving end, read the correct number of bytes for your data type and do the inverse conversion (unflatten to string, or typecast again).
