With RAM, timings and clock frequency are tightly coupled. In specific scenarios with high timings and clocks you can actually make performance worse than with lower clocks and faster timings.

You need to reduce timings and increase clocks. CAS latency or 'ticks' are effectively an amount of clock cycles that the CPU & Memory Controller has to wait for the RAM to complete various tasks. A simple formula to use to calculate your effective true latency is as follows:

Single Word Read Latency:

CL * 2000 / DDRrate

Four Word Read Latency:

CL * 2000 / DDRrate + (3*1000 / DDRrate)

Eight Word Read Latency:

CL * 2000 / DDRrate + (7*1000 / DDRrate)

Take for example CAS 14 RAM at 3200Mhz

Single Word Read Latency:

14 * 2000 / 3200Mt/s = 8.75

Four Word Read Latency:

14 * 2000 / 3200Mt/s + (3*1000 / 3200Mt/s) = 9.6875

Eight Word Read Latency:

CL * 2000 / 3200 + (7*1000 / 3200Mt/s) = 10.9375

Now lets use a practical example:

Flare X F4-3200C14D-16GFX

DDR4-3200 (PC4-25600)
CL14-14-14-34
1.35 Volt
14 * 2000 / 3200 =8.75

Flare X F4-2400C16Q-64GFX

DDR4-2400 (PC4-19200)
CL16-16-16-39
1.2 Volt
16 * 2000 / 2400 = 13.32 <---- slower

HOWEVER look at this 4133MHZ kit with high CL19 timings:

Trident Z F4-4133C19D-16GTZKWC

DDR4-4133 (PC4-33000)
CL19-19-19-39
1.35 Volt
19 * 2000 / 4133 = 9.19 <--- still faster than the 2400 kit but actually slightly slower than the 3200 kit