What are the benefits if you change the tire size?

1989 BUICK REGAL
59,000 MILES • 2.8L • 6 CYL • 2WD • AUTOMATIC
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OLDGMLOVER
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I just found out that I can no longer get white wall tires in my factory size, but they are still being made in other sizes. I would like to be turn the right direction as to what size I can change to because I want to keep the appearance of my vehicle staying stock and if I can find another option, I want to go with that.

My factory tire size is 205-70r14. I have been using a tire calculator comparing sizes online that do come in white walls. But I am not an expert yet, I am just starting out in the field.

I know changing to a different size as it’s pros and cons. You got to calculate the width and ratio to make sure there’s enough room between the fenders and making sure it doesn’t wear out major components due to adding on more weight putting a strain on the transmission and suspension components. It can also screw around with your speedo. I was told switching to a bigger size can cause the tires to rub against the fenders while turning and riding over bumps when braking causing the tire to rub against the top fender. I don’t care about speedometer difference. I just don’t want to have issues with my transmission or suspension wearing out faster.

I will never want to change my vehicles steel rim size. I just want to stay with 14s and find something suitable with white walls. If you can help me calculate that I would appreciate it.

Before I call the shop that does my specialty work, I wanted to ask you guys because you are also experts and wouldn’t steer me in the wrong direction when it comes to safety and giving good advice.

I would appreciate any help. This is the tire calculator I was using for reference.

https://tiresize.com/comparison/
May 26, 2022 at 3:56 PM
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SQM
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Hello,

Those white wall tires are getting harder and harder to come by given such a limited production.

For your vehicle in order to stay within reasonable tolerance you can use these sizes:
These 2 would be the closest match:
215-65r14
195-75r14

You can also use (but little more off of the factory size)
185-75r14
215-70r14

Keep in mind all these sizes are a little different that the factory in overall size but stays within a reasonable amount.
The trick might be finding these in white wall.

Let me know of any questions.
Thank you.
May 27, 2022 at 3:12 PM
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OLDGMLOVER
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I was thinking about using 195-75r14, but I heard it would be like driving on ice skates because the width would be much slimmer than the factory tires.

Then i was thinking about going with 205-75r14. Would that cause any rubbing to the fenders when turning or braking? I have seen these cars with them, and it looks bigger. It makes me think it would be rubbing a lot.
May 29, 2022 at 12:18 PM
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SQM
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205-75r14 will be noticeably taller and the speedometer will read less than actual speed.

I don't think it will rub. What you can do is turn the wheel all the way to one direction and measure the closest object. As this size will be about .8" taller in diameter so it will gain .4"
May 29, 2022 at 4:23 PM
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OLDGMLOVER
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What about the size you given me above? 215-70-r14? Will it cause transmission strain or suspension wear faster? Won’t rub at turns or braking? That’s the one that looks close enough to factory. It is spot on with the width and only 2% off with speedo. Ride height diameter isn’t that much of a difference either.
May 31, 2022 at 8:01 AM
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SQM
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The 215-70r14 is close to the factory and should not have any adverse impact on the drivetrain, as you said it is only a 2% variance .
May 31, 2022 at 9:14 AM
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OLDGMLOVER
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Good to know and no rubbing either near fender wells correct?
May 31, 2022 at 9:21 PM
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SQM
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It shouldn't rub. I would still suggest you do a check as we don't know how much is the suspension/springs has sagged over the years. Turn the wheel all the way either direction and check for clearance. You want to have about 2-inch gap at the closest spot. This will be adequate to work for the new tire.
May 31, 2022 at 9:49 PM
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OLDGMLOVER
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So, I would measure the tire to the fender well and that’s the reading I should get.
Jun 1, 2022 at 6:31 AM
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SQM
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You should have at least 2", should be more in reality.
Jun 1, 2022 at 2:53 PM
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OLDGMLOVER
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So compared to the 205-70r14 it shouldn’t be over 2-5 inches with the 215-70r14. And since you said that’s almost factory I should be good.
Jun 30, 2022 at 10:19 PM
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SQM
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Yes. It is the closest to the factory size. Should work out just fine.
Jul 1, 2022 at 10:38 AM