Tires: old tire size to new, size tire, vintage car

Question
I have some old tires that are 4.25x4.5x18. I would like to know what size tire this would be in comparison in todays tires.

Answer
Terry,

The equivalent would be a 105/92R18 - and even then I think there may be a problem with the rim / bead fit.  Obviously this size isn't made.  But if you are intrested in finding a tire, I suggest you contact Coker Tire.  They supply tires for vintage car and should be able to find something that works.