16 inch to 17 inch tires change the speedo!
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From: Mercedes Norte, Heredia, Costa Rica
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Re: 16 inch to 17 inch tires change the speedo!
You don't change anything by going from a 16 to a 17 inch rim. It's when you change the overall tire diameter that you have to worry about the speedo. You need to change the speedometer gears in the tail of the transmission to correct it.
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From: saint cloud,florida
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Re: 16 inch to 17 inch tires change the speedo!
via a calculator on a camaro site
going from 16 to 17inch tires changes the true speedometer readout
if your speedo reads you're going 65 with stock 16s thats 65mph
change your wheels to 17 inch and then
your speedometer reads 65 but you are actually
traveling at 69.06mph
Is there a simple adjustment I can do to the speedo
in order to correct this difference and is this adjustment
worth the effort or could it screw everything up ?
going from 16 to 17inch tires changes the true speedometer readout
if your speedo reads you're going 65 with stock 16s thats 65mph
change your wheels to 17 inch and then
your speedometer reads 65 but you are actually
traveling at 69.06mph
Is there a simple adjustment I can do to the speedo
in order to correct this difference and is this adjustment
worth the effort or could it screw everything up ?
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From: Bertram (outside Austin), TX
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Re: 16 inch to 17 inch tires change the speedo!
If the overall tire size doesn't change, your speedometer won't read differently.
I went from a 245/50R16 to a 315/35R17 & the speedometer still reads correctly.
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Re: 16 inch to 17 inch tires change the speedo!
Last edited by grassyflats; Feb 11, 2010 at 11:56 PM.
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From: Bertram (outside Austin), TX
Car: 87 GTA
Engine: L98
Transmission: 700R4
Axle/Gears: Dana M78 3.27 posi
Re: 16 inch to 17 inch tires change the speedo!
And a 245 fits a 8" wheel. Too narrow for a 9.5" wide wheel. You need a 275.
275/45R17 = (drum roll please....) 25.7"!
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Re: 16 inch to 17 inch tires change the speedo!
You are correctI did not remember to double check -the posted info on another thread
was incorrect -so now I completely understand this mod does not effect
the speedo
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