How much total loading times does Wii U version save on 32 track runs?

you can't say a specific time, because every disc drive has not the same speed. sometimes it's faster and sometimes slower, so we can only say the wiiu disc drive is faster than the wii one.

-Every specific person's drive is different you're saying? That's kinda obvious but at the same time...... wouldn't dthe difference only be like a few nanoseconds?

I just need a general idea of how much slower it is.

more than a few nanoseconds. THere is less input lag on the wii u i think, so that also has a factor. However, if you're used to wii input lag that might get fucked up on the wii u.