Rims and tires

Ok what is the biggest tire I can put on my 69 DART without mini tubbing it. I had a 245 60 14 up next to it and it looked small. I want a 15" rim but not sure what size tire I can go with on that rim. I brought this car home in pieces from Michigan in August. I'm so close to getting it done. I've set a goal to get it going before the first snow here in ohio. Doesn't leave me much time. I'm so excited. :dontknow: