Since the emulation of Chankast is all about CPU performance and that will define how fast your games go. You can only influence a better framerate with the under/overclock keys within chankast. This can be done with the +/- on the keypad. The results will vary and the framerate still will fluctuate since it isn't limited and there's no frameskip.
As for a modified version of Chankast with the name Chankast Utilities there's an integrated tool called Speed Pig. I'm still not sure what it does to gain extra speed but guess that it will up the Front Side Bus of the system giving a few more frames per second.
Also don't use too high graphical settings if you force them in your drivers. When the settings are too high for the card itself to handle the cpu takes over to calculate instructions. This way a normal pc game still performs at these high quality settings since there's spare CPU time left. As for Chankast there isn't any spare CPU time left because it's an emulation and it uses all it can get. I have no proof if this actually works for Chankast.
Does anyone uses this Speed Pig tool and knows what kind of extra speed it gives? Maybe also how it works and if it's safe to use.