Anyone have a link to a tire size calculator?? One where you can enter a tire size and get the total diameter....I may have a bad tire on my 67 300 and I may have to find a replacement. They no longer make any tires in my current size...245/70x15.

You could try the Tire Rack. There's a couble of new tires on the bag in the size you have on your car.

Hmmmmmm, I just called Tire Rack this morning and they said they had NO tire available in 245/70x15.

I'll check again, of course...I'd hate to have to spend the money to get a new set of wheels and 4 new tires just because one tire is bad!! Must be a better way, at least in the short term until my 3 other tires are no good.

Here's what I've got...67 300 'vert. 15 x 7 Wheel Vintiques repo Mopar wheels with 245/70x15 Yoko Avid S/T tires on them. These Yokos are very good tires and the size is perfect for keeping my axel ratio and speedo same as it was stock...while getting a better tire and more tread area on the road...

Try this link:
http://www.miata.net/garage/tirecalcold.html
I use this one all the time at work and at home.

Based on the info on the tire calculator,you may have to go with a 2357515 tire to maintain your desired speedo/gearing

Thanks CBarge....should have just asked you on the C body site, but this site has a lot more activity...

This site is great for rims & tires

http://www.rims-n-tires.com/rt_specs.jsp...xt1=&text2=

look on EBAY