I have 14 x 6 Rally wheels, and want to put some BF G's on the car. What is the size I should use if the car had F 70's originally? I want to use as close to the original size tire as possible. Thanks.

This may help.
http://www.turbinecar.com/tires.htm

I just got 215/65/15 for my 15x7 rally's. They are 1/2" shorter than E70/15 originals. Look in Summit catalogue. They have the T/A radials with dimensions listed.