Its time for new Tires on my 55 chevy. I have been running BFGoodrich TA Radials and very happy with them 185 70 14 on the front 235 70 15 on the rear thay no longer make the 185 70 14 these are the tires I have been using for years and at a loss as to what to go with now. Any one have a idea. I drive this car on cross country trips so i want to stay with Radials
nwbhotrod... I 'did the math' on the 185/70r14... 185*.70 (tire aspect ratio) = 129.5 divided by 25.4 mm/inch = 5.09 inches... which gives us 2 * 5.09 = 10.18 + 14 inch rim = 24.18" tire height. On the BF Goodrich webpage for TA radials: http://www.bfgoodrichtires.com/tire-selector/category/hot-rod-tires/radial-t-a/tire-details the smallest (overall tire diameter) 14" tire they list is the 215/60r14 with a tire diameter reported to be...24.2. The trade-off with this tire would be 215 - 185 = 30mm divided by 25.4mm/inch = 1.18" wider on the treadface. So, the 215/60r14 would give the same tire height, just a slightly wider treadface. The other tire, 235/60r15 is listed on that same page and is still available. Gotta56forme/Scott
The numbers 185 & 215 are the width of the sidewall at it's widest point (aka "section width), not the tread face width. Tread face widths often vary by manufacturer, and/or tire model, even though the tires have the same section width dimension. Tire Rack has excellent information available on their website for every tire they sell giving the specifics of diameter, section width and tread face width.....and more. Ray
I humbly stand corrected... I googled metric tire sizing and that first number is indeed section width. For some reason, I thought it referred to treadface width, all these years. I believe the math is still the same.
One thing to add to this good information is when you're selecting a tire for an application where clearance is tight you have to know the rim width the mfgr used in determining the tire's dimensions because the same tire will vary depending on the width of the rim its mounted on. Also, as Ray mentioned, you need dimensions for the actual tire under consideration rather than assuming the stated size will give you a specific set of dimensions. They're all nominal, and you could find that one tire sized as a 185 might have an actual section width of 180 while another make or style of 185 could have a 190 section width. Same goes for the aspect ratio. There are variations there as well, depending on who made the tire and which particular tire it might be within a single manufacturer's lineup. The only dimension you can count on as agreeing with the stated size is the rim diameter.
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