Every CPU will behave differently. Also, your cooler, case airflow, ambient temps, and mobo vrms will have an impact on overclocking. Because of these many variables, we can only give rough estimates.
A good overclock most 1600s should hit would be around 4ghz. Some CPUs may get more, some less.
I would try 3.9ghz at 1.35v and then go from there.
Remember, you want the highest frequency at the lowest stable voltage. I would run Prime 95 small fft for around 1/2 hour to test CPU stability after each overclocking setting change.
Avoid voltages over 1.4v and temperatures above 80-85c to avoid diminishing the lifespan of the CPU much.