This guide will help you find the correct size tire for your car based on the current system of sizing tires vs. the old way.
First, let's decode the new sizing system so you understand it better. Let's start with a common size...P205/60r15.

The "P" preceding the numbers indicates a passenger tire.
The "205" is the cross sectional width of the tire in millimeters.
The "60" is the aspect ratio, the ratio of the sidewall height to the cross-section width.
The height of this tire's sidewall is 60% of the tire's width.
The "r" stands for radial.
The "15" is the rim diameter in inches.

The following pairs the most popular older tire sizes to the new tire sizes. Note that these are as close as possible & actual tire sizes may differ slightly between manufactures.
6.95-14=====P185/75r14

7.35-14=====P195/75r14

7.75-14=====P205/75r14

D70-14=====P205/70r14

E70-14=====P205/70r14

F70-14=====P215/70r14

D78-14=====P195/75r14

E78-14=====P195/75r14

F78-14=====P205/75r14

E60-15=====P215/60r15

F60-15=====P225/60r15

G60-15=====P235/60r15

F70-15=====P215/70r15

- Roger Kizer