This was just before the two 170 mph runs. 4s with APC 5050 props. In the run, you can see the quad lose a little altitude but I graphed the altitude against velocity and only reported the velocity just before altitude loss.
Blackbox log: https://drive.google.com/file/d/0Bw5AmHq7h72NN3o2MkdUTFFGZ1E/view?usp=sharing
Decoded GPS with graph: https://drive.google.com/file/d/0Bw5AmHq7h72NZS1WeDhqTnl4LXc/view?usp=sharing