Wheel and tire rec's for 67 Dart
If you looking for a safety skip 15" tires and go to 17". The variety of compounds are much greater, cheaper and the case and tread designs are light years ahead. With the BBP swap you did in the front, the front trac got wider, so you need more backspacing (or positive offset). I run a 17x7 in the front with a 4.75 backspacing, but I run a staggered set up of 215/45/17 front and 245/45/17 in the rear on a 17x8 rim with a 5.375" backspace on a A-body 8-3/4 converted to BBP with 11" drums. A lot of folks have ran a 225 or 235 wide tire all the way round on 67-69 Darts, but wheel backspacing is key. All the other A bodies have different fender wells, so what fits a Duster, Barracuda, etc may not fit your car. 67-69 Dart are probably the most difficulty to fit without rolling fenders, offsetting springs, etc. Ideally for your rear source a 66-67 B-body 8-3/4 and use off the shelf 17x8 1994-2004 Mustang wheels. To rotate you need to jack the rear of the car up and let the rear axle hang so the wheel/tire will come out.
If you want to stay with 15" tires, a 15x7 with 4.5 back spacing and a 225/60/15 is a good combo. Wider 15" wheels with more back spacing cause issues of starting to hit the upper A Arm and tie rods.
Below is my car to give you an idea of fit. I've since swapped to Dr Diff 13" front brakes, another good reason for 17" wheels.
If you looking for a safety skip 15" tires and go to 17". The variety of compounds are much greater, cheaper and the case and tread designs are light years ahead. With the BBP swap you did in the front, the front trac got wider, so you need more backspacing (or positive offset). I run a 17x7 in the front with a 4.75 backspacing, but I run a staggered set up of 215/45/17 front and 245/45/17 in the rear on a 17x8 rim with a 5.375" backspace on a A-body 8-3/4 converted to BBP with 11" drums. A lot of folks have ran a 225 or 235 wide tire all the way round on 67-69 Darts, but wheel backspacing is key. All the other A bodies have different fender wells, so what fits a Duster, Barracuda, etc may not fit your car. 67-69 Dart are probably the most difficulty to fit without rolling fenders, offsetting springs, etc. Ideally for your rear source a 66-67 B-body 8-3/4 and use off the shelf 17x8 1994-2004 Mustang wheels. To rotate you need to jack the rear of the car up and let the rear axle hang so the wheel/tire will come out.
If you want to stay with 15" tires, a 15x7 with 4.5 back spacing and a 225/60/15 is a good combo. Wider 15" wheels with more back spacing cause issues of starting to hit the upper A Arm and tie rods.
Below is my car to give you an idea of fit. I've since swapped to Dr Diff 13" front brakes, another good reason for 17" wheels.
