Foose 17x8 4.5 bs on 67 Dart ?

The more you lower the car, the further away from the fenders and quarters the tires have to be because the wheels have to be inside of all the bodywork. If you car sits up high, you can get away with wider tires/less backspace because the tires can only hit the body when the suspension is compressed.

All of the numbers that I typically give are for lowered cars, because I'm using my own lowered cars as reference. On a '67 Dart with 15" rims and 15x7's and 15x8's though there isn't much you can do. Your backspace is limited by the 15" wheel diameter in the front, not to mention the backspacing that 15" rims are usually offered in. The Ansen sprints are only offered in 15x7 with a 4" backspace and 15x8 with a 4.5" backspace. Both of those are 0 offset rims, when really you'd like to have +6 or even +12. With those specs the biggest tire you'd be able to run up front is a 215/60/15, in the back probably a 235/60/15.