Need some help with wild grapes

[david83]

I've started a small garden this year and got to thinking, I have some very well established wild grape vines of indeterminate variety that I would like to help become productive. These vines produce some very small clusters of grapes that are about 1 millimetre in diameter but never anything any larger. Is there anything I can do to help these vines produce larger grapes that I can use to make various preserves?
I suspect they are muscadine vines but I'm not certain. I am able to make some really good jelly from vines at a friend's house but would like to have my own vines being productive.
For those that insist, I used the search method and found only three threads that had nothing useful for my education. Please help.
Thank you!