I have some old H60 15's on the rear of my 53 and want to upgrade them to some new radials. Can someone tell me what the equivolent size is using the new coding system (like a 25560r15 or something like that)

 

I think it equals 225/60R15. It seems like 235's are equal to the old L's.

 

This link says H60-15 converts to either P235/70R15 or P255/60R15
depends on aspect ratio or diameter you prefer. Both tires are the same width (10") but the P235/70R15 diameter is a little over 28.5" where as the P255/60R15 diameter would be a little over 27.5"

http://www.geocities.com/MotorCity/2398/tires/TIRE.HTML

 

Great link Pat, thanks!