Ddr3 1600 (pc3 12800)

I have Corsair Vengeance on my MSI Z77A-GD55 mobo. Currently it is running at DDR3-1333 but the memory is rated at
DDR3-1600.
The CAS timings are default at 9-9-9-24. (Two 4 GB sticks Dual Channel) 1.5v

I understand that I need to change the DRAM Freq in the BIOS and the CAS timings as well.

The MOBo has ClickBIOS II installed.

My question is this: I know where the DRAM Freq settings can be changed but have no idea how to change the CAS timings or what to change them to in order to get the RAM to run at DDR3-1600.

Is anyone familiar with this procedure?

Thanks in advance,

MK