these were on my dad's '97 blazer when he bought it, i have them now and am planning to put 235-60-15's on them. they have a dual-bolt pattern so they fit either 4-3/4 or 4-1/2 bolt patterns. they take "et" lug nuts, had to order those, couldnt find at any local parts stores. dont have the bolts that hold the center covers, missing one anyways and one bolt had broke off in the rim. from wheat ive been able to figure out these were sold by sears and made by american racing. found one center cover on ebay, for $40.00 going to switch these between 3 vehicles, the smaller size will make my 3.73's seem like 4.10's, might make it easier for my daughter to learn how to drive, also plan on having these on the '77 granada. and until i get some better rubber on the stock rims for my wife's S-10 blazer, thay will probly spend some time there and make the 3.42 gearing in it more likeable when towing the trailer. 2 are polished up in this pic and the other 2 were awaiting poilish. all done now and looking like chrome.

 

what size tire was on the rims, better yet, what size do you have now? the diameter of the rim has less to do with gear ratio, than the overall diameter of the tire. are you talking rotating mass or what? to respond to this we would need the diameter of whats on the car or truck now, and what your putting on. i was under the impression that for every tire size you go up, you would loose 1 point in gear ratio. same would be true than, if you drop tire size, you would increase gear ratio, 1 point for every tire size. example.... 245.75.16s with 4.10 gear ratio, if you change to 256.75.16s, would have a 4.00, or darn close.