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Changing tire size,What would happen

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Old 08-25-13, 10:13 AM   #1
BgLftyinaz
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Default Changing tire size,What would happen

Currently stock tire is 215/45/17 with these specs
Michelin Primacy MXM4
500 AA A 24.7 overall dia. and 844 revs per mile
http://www.tirerack.com/tires/tires....=yes&tab=Specs
Looking to replace with 205/50/17
Continental PureContact with EcoPlus Technology
700 A A 25.1 overall dia and 828 revs per mile
http://www.tirerack.com/tires/tires....ECXL&tab=Sizes
I believe speedo with be off .Will odometer be off as well ? Also what I'm hoping for is better LRR and beter fuel mileage.

Also with tire be slightly taller ride should be smoother.


Site comparing size difference
http://www.1010tires.com/Tools/Tire-...5R17/205-50R17
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Old 08-26-13, 02:50 AM   #2
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your ride quality will improve.

your fuel economy, maybe.. skinnier tyres vs. taller tyres.

your speedo will off, so will your Odo.
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Old 08-28-13, 02:21 PM   #3
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Stock tire
Sidewall 3.8 in
Radius 12.3 in
Diameter 24.6 in
Circumference 77.3 in
Revs per mile 819

New Tire
Sidewall 4.0 in
Radius 12.5 in
Diameter 25.1 in
Circumference 78.8 in
Revs per mile 804

Speedometer on new tires will read 1.8% too slow.
When the speedo says 60 mph, you will be traveling at 61.1 mph
ABS will actually increase your braking distance
Both tires weigh the same so MPG gains could be seen if driven conservatively.
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Old 02-18-15, 11:43 AM   #4
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Has anyone used 205/60R60 size in CT? Specs would be

Sidewall 4.84"
Widht 8.07 "
Diameter 25.7"
Revs/mile 785

I wonder if it fits and does anything to the ride comfort compared to stock 205/55R16.
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Old 03-03-15, 05:10 PM   #5
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I guess I'll disagree with the previous posts by saying the new tire size will actually be more accurate in regards to the speedometer.

With a little research, you will realize that by default, the speedometer reads fast. When in doubt, measure it with few GPS devices. You will be amazed to see 70mph is actually 67.


EDIT:
Stock = 215/45/17
You are proposing 205/50/17 which is a 1.8% change.
I propose you go 225/45/17 since it will be only a 1.4% change.

The 225 will also give you a smoother ride (higher sidewall), but it will have a lower risk of making your speedometer read too low.
You may of course have slightly reduced MPG figures, but in theory you should also gain more traction due to wider tires.

Last edited by edgalang; 03-03-15 at 06:19 PM.
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Old 03-05-15, 08:37 AM   #6
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Quote:
Originally Posted by edgalang View Post
I guess I'll disagree with the previous posts by saying the new tire size will actually be more accurate in regards to the speedometer.

With a little research, you will realize that by default, the speedometer reads fast. When in doubt, measure it with few GPS devices. You will be amazed to see 70mph is actually 67.


EDIT:
Stock = 215/45/17
You are proposing 205/50/17 which is a 1.8% change.
I propose you go 225/45/17 since it will be only a 1.4% change.

The 225 will also give you a smoother ride (higher sidewall), but it will have a lower risk of making your speedometer read too low.
You may of course have slightly reduced MPG figures, but in theory you should also gain more traction due to wider tires.
Going from 50 to 45 series tires means a lower sidewall, not higher.
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Old 03-06-15, 04:00 PM   #7
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Quote:
Originally Posted by Raidin View Post
Going from 50 to 45 series tires means a lower sidewall, not higher.
This is not always the case, as that is a ratio and not a set amount.

Regardless, I believe you read my response wrong. I wasn't talking about changing the sidewall ratio. I was pointing out the fact that going to 225/45 from OEM 215/45 will give you a higher sidewall.
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Old 03-08-15, 09:01 AM   #8
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Quote:
Originally Posted by edgalang View Post
This is not always the case, as that is a ratio and not a set amount.

Regardless, I believe you read my response wrong. I wasn't talking about changing the sidewall ratio. I was pointing out the fact that going to 225/45 from OEM 215/45 will give you a higher sidewall.
Oh it's a ratio, I see! You're right, my mistake, thanks for clearing it up!
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