No, it is not recommended for overclocking. When overclocking, it reaches a maximum temperature of 89C in the CPU-Z stress test. Tested with a Core i7 4970K. It would fail the test with Prime95. 
http://www.guru3d.com/articles-p...
http://www.gamezoom.net/artikel...
I have an Intel i7-7700K and Zalman CNPS 9900 MAX. The temperature highs are at 87C on Prime95 with a Core Speed of 4600 MHz (multiplier 46x) and Core Voltage of 1.312. In the CPU-Z stress test it has a maximum temperature of 71C.
https://www.galaxus.ch/de...