Pi2 Overclock settings?

H3X1C

So I fancy getting a bit more out of my pi and want to run some n64 games like mario kart although currently I get quite bad lag.

I've looked into overclocking and can't find any solid info to go off for the Pi 2 model b.

I have also read you can edit the memory split to give more ram to the GPU but unsure of what values to use.

Now I'm wondering if anyone has suggestions for me in terms of settings. Currently I have the below overclock settings:

over_voltage=4
arm_freq=1075
core_freq=500
sdram_freq=500
gpu_mem=400
force_turbo=1

Any help is much appreciated :)

BuZz