Yeah, that seriously sounds like mucho problemos.
On pure intuition alone, I'd assume you came up with the idea to mix coke with K - in whatever manner - after experiencing the mind-numbing/body-detaching effects of high-dose K, yes?
In a thoughtless, superficial way, your plan sounds like it makes sense:
"Feeling stuck in your K-hole? Can't move much, let alone form coherent words? Do you drool every time you try to take a drag of your cigarette?
Well, suffer no longer, with.......COCAINE!!" dingdingdingding womp womp wowowoweee
A silly advertisement, though similarly misinformed, on a general level, apparently. While your question was regarding the ideal ratio of K to C, it's already looking like most of the posters will be condemning your implied plan, or attempting to dissuade you from trying it [again] - if you haven't already.
That combination has DANGER written all over it, in a language called "Common Sense" lol
I am not implying that you lack common sense - I am, however, pointing out the tendency for many drug users to discard certain of their notions of common sense in relation to drug use, as I, myself, have...many times...all for the sake of something better, more intense, funner... But you know K, right? You know it sure as hell isn't worth damaging your body severely for, is it? Naaaah.....
Please be careful, no matter what you do.