New tires load/speed rating question

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YowzaZ31
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Joined: Thu Mar 26, 2015 11:16 am
Car: 86 N/A

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Looking to buy set of 4 BF Goodrich Radial T/A’s and found a really good deal for my ’86 N/A. I don't drive it much, put less than 2k miles on it per year. The tires that are on sale have a load/speed rating of 93/S (up to 112 mph). My '86 owner’s manual calls for the tires’ load/speed rating to be 90/H (up to 130 mph).

Will I have an trouble with the these new tires if I run with them?


YowzaZ31
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Joined: Thu Mar 26, 2015 11:16 am
Car: 86 N/A

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My second question would be ..... is there another size tire other than the 215/60R 15 that I can safely run with??

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evildky
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The S rated tires are fine as long as you don't plan to do sustained driving north of 112 mph. 205/50 R15 is a more common size. On the stock 15 x 6.5 wheels you can run anything from a 195 to a 225 width without issue and 45-60 % aspect ratio. If you up size the wheels you'll find more tire options but as the size goes up so does the price.

YowzaZ31
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Joined: Thu Mar 26, 2015 11:16 am
Car: 86 N/A

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evildky:
So any of these sizes will work??? Any more not listed?

Tire alternative chart has:
195/65R 15 @ -0.8%
205/65R 15 @ +1.2%
225/60R 15 @ +1.6%

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evildky
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I'd personally go for a 225 50 15, very common size, it'll lover the car a bit, increase contact patch and reduce the sidewall and get rid of the bg sidewall flex.

YowzaZ31
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225 50 15 on the stock 15 x 6.5 wheels???

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evildky
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Location: Louisville, KY
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I meant to say 205 50 15, but the 225's would work too just might crown the tread a bit

BadQ45t
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Actually I have run 225/50 15's for about 20 years now and they work great. I have had others say that it would be too wide on the rim but they fit just fine and work just fine. I have a set of Bridgestone SO3's on there right now that are finally coming off in favor of new 16x8 Enkei Comp wheels with 225/50 16 tires.

There are a few choices left in the 225 size on the HR speed rating but none in ZR or above unless you want autocross tires.


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