Any idea of what Coker radials translate to the 8.00 x 14 and 8.50 x 14 bias ply?

Those width numbers are the tread width, the more important number is the section width. The Coker 800x14 are 8.1 wide, the 850-14 are 8.35 wide.

For modern sized, the section width is the first number of the tire, but it's in millimeters, not inches. 25.4mm = 1in.

I could go into a dissertation on tire sizes, but I've done that before (do a search here on tire sizes, you'll find it. ). The bottom line is that most folks go with either 215/75R14 or 225/75R14. The former is supposed to be close to the 800's, the later the 850's. In reality, they are each a little too short and a little too wide, but they are the best match. I believe that's what Coker recommends as well. They have a handy conversion chart here.

Discount Tire has a neat tire size calculator that can help too.

Here is another GREAT tire sizing calculator I have saved over the years:



It ran these facts on these 2 tire sizes.

225/75R14: VS. 215/75R14:

Sidewall 6.6" ~~~~~~~ 6.3"
Radius 13.6" ~~~~~~~ 13.3"
Diameter 27.3" ~~~~~ 26.7"
Circumference 85.7" ~~ 83.9"
Revs/mile 739.0" ~~~ 755.0"
MPH 60MPH ~~~~~~ 58.7MPH

The speedometer on a car running the 215/75R14 tires (compared to a stock 225/75R14 tire) would be reading 2.2% too fast....