I've read all the other answers and I don't think they're great advice. (No offense.)

This is IPS but also general business. You need to keep that in mind as you approach it.

##In this situation

Be patient, accept that he won't get back to you soon, and be prepared for him to never get back to you at all on it. You can't win them all, and in life you're going to hear a lot more "no" than you hear "yes" and that's okay. It's something you must be able to accept without having it affect you negatively.

##In future situations Be patient, and always give a follow up time. "That's great, can you get me the info by Thursday?" or "I will set up a time for us to talk again next week, please send me relevant research material before then so I can review it and we can discuss it."

In both situations, be very patient. Patient persistence is how business happens. And having followup deadlines show you know what people need to do, how long it will take for them to do it, and that you have the management skills necessary to keep them in line. And if someone is fussed by having time frames in which they need to get things done, you don't want to get into business with them anyway. Better to not complicate your friendship with such things.

Should you call? Probably not. That doesn't highlight your ability to be patient, and will only lead to you being ignored when it's actually time sensitive.

Should you text again? Probably not. If it doesn't work out, that's okay. It's important to not get too attached to an idea until you see it's going to be concrete.

I've read all the other answers and I don't think they're great advice. (No offense.)

This is IPS but also general business. You need to keep that in mind as you approach it.

In this situation

Be patient, accept that he won't get back to you soon, and be prepared for him to never get back to you at all on it. You can't win them all, and in life you're going to hear a lot more "no" than you hear "yes" and that's okay. It's something you must be able to accept without having it affect you negatively.

In future situations

Be patient, and always give a follow up time. "That's great, can you get me the info by Thursday?" or "I will set up a time for us to talk again next week, please send me relevant research material before then so I can review it and we can discuss it."

In both situations, be very patient. Patient persistence is how business happens. And having followup deadlines show you know what people need to do, how long it will take for them to do it, and that you have the management skills necessary to keep them in line. And if someone is fussed by having time frames in which they need to get things done, you don't want to get into business with them anyway. Better to not complicate your friendship with such things.

Should you call? Probably not. That doesn't highlight your ability to be patient, and will only lead to you being ignored when it's actually time sensitive.

Should you text again? Probably not. If it doesn't work out, that's okay. It's important to not get too attached to an idea until you see it's going to be concrete.