Let me start by saying: the responses you're going to get on this post are going to range from poster to poster. Each of us has different experiences in the time frames we deal with, so there isn't necessarily a "right" or "wrong" time frame.
With that said, though: while there might not be one correct time frame per se, there IS a success percentage with each one. What I mean is, the girl retention rate for someone who calls his dates the very next day to ask for a date is going to be different that the rate for someone who calls his dates after waiting x-amount of days. There are various psychological reasons that go into this, the majority of which I will have to save for a later post
What I have found to be true in my own testing of various call days (calling the next day, calling after 2 days, after 3 days, etc.) is that my highest girl retention rate - i.e. the girls that would date me for long periods of time - were the girls I'd call FOUR DAYS after a date to set up another date.
It's not about getting the girl to go out with you a 2nd or 3rd time. You need to be thinking about ways to keep her interest over a longer period of time. In order to do that, you need to spread out the dates.
If you go out on a date with a girl, then call her up the next day to ask her out on a date for the next day, then see her again, then ask her out the day after that... by the end of the week you'll have gone out with her 3 times already.
Because of this, you'll only have a day or two between dates for other things in your life to happen. Consequently, when you go out with her you'll have very little to talk about, other than things you've already said to her before. This will make you appear boring to her, and by the 3rd date she'll feel as though she knows everything about you. Now there's nothing new for her to explore, and she's ready to move on to someone else.
Contrast that with a guy who goes on a date with her, then calls her 4 days later to set up for a date 2 days after that. When they meet up, they now have SIX DAYS worth of stuff to talk about. When she hears his stories, she's going to think "Wow, he does a LOT of cool stuff when I'm not around him - he's not boring at all, AND he has a life outside of me!"
I also find that waiting 4 days is a good way to gauge her interest. For any girl that's been REALLY into me, I have yet to go a full 4 days before SHE hits ME up and asks ME if we can get together. And when she does, we make arrangements for the time and place to meet, then I go NC until the date.
So, that's my experience. Like I said, I'm sure others will probably come on here and tell you "you can contact her within a day or two, bro, otherwise she won't know you're interested and bail." I've found the opposite to be true time and time again: when they like you, they'll wait for your call; when they don't like you, they won't care that you called; and if you call too soon, the one that might like you will start to get annoyed by you.
Hope this helps!