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Speedometer correction -- front or rear tires?

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Old 03-29-2003 | 08:03 PM
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Killer '01 SS's Avatar
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Default Speedometer correction -- front or rear tires?

I'm going to be putting 275's on the front and 285's on the rear. The tire diameter for the 275's is 25.7" and the diameter for the 285's is 26.0". In LS1_Edit, do I use the rear tire diameter in the "Tire Diameter" field for speedometer correction? Or the front tire diameter?

<small>[ March 29, 2003, 08:04 PM: Message edited by: Killer '01 SS ]</small>
Old 03-29-2003 | 08:24 PM
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Default Re: Speedometer correction -- front or rear tires?

The vehicle speed sensor is monitoring driveshaft revolutions... So you'd need to use the rear tires.

I'm running 165R15's in the front, 295/50-15's in the back (about 26.5" tires). The 26.5 setting is what makes it read the correct speed.

HTH,

Andrew
Old 03-29-2003 | 09:02 PM
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Default Re: Speedometer correction -- front or rear tires?

Thanks for the quick reply, Andrew. I didn't think the front wheels had anything to do with the VSS on modern vehicles, but I just wanted to be sure. <img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />




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