In the stock app, messages are split after 160 characters. You can go into settings and change it back to send as one message.
When you do that it's forced to send as an MMS no? The last time I tried that, I had to have data turned on in order for it not to split it. And then, my friends without a plan to receive MMS were unable to receive my messages. Only way for me to send 160+ without data was to have it split, but then I ran into problems where the second/third message will be delayed.