Calculating tire size

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mikel
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Calculating tire size

Post by mikel »

http://www.gordon-glasgow.org/tirecalc.html

or, use this handy tire revs per mile calculator:
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charala
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RE: Calculating tire size

Post by charala »

I run staggered tire sizes; I assume I should use the tire size info from my rear tires for this calculation...am I correct? :punisher:

Thanks,
-Chris
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tuningss
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RE: Calculating tire size

Post by tuningss »

Yes, the rear tires are the ones you use.
Certified Advanced EFI Calibrators for Ford, GM and DCX/Jeep Vehicles.
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Gointopless
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RE: Calculating tire size

Post by Gointopless »

There are all kinds of apps for smart phones too..
bugattis4
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Post by bugattis4 »

thank you!!!
SFDBR14
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Post by SFDBR14 »

These calculations will get you in the ballpark. However, it has been my experience that your speedometer will be off by about 5 mph @ 80mph. I used my GPS to help me fine tune the value for the revs per mile in the tune. I ended up having to use a value of 880 revs per mile for a set of 275/40 R18 wheels. If you run this through your calculations it will tell you that you should be running 756 for the revs per mile.
2012f1503.7
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Joined: Tue Oct 07, 2014 1:23 pm

Re: Calculating tire size

Post by 2012f1503.7 »

I'm trying to do the tire Change on my truck and was wondering do I put in the revs per mile in the tire circumference? I'm running a 35x12.50x20.
isato01
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Joined: Sun Aug 10, 2014 7:05 pm

Re: Calculating tire size

Post by isato01 »

sup bruh ,im tried to recalibrate my speedo but it asked for diameter and mine says is 100.25 for a set of 275/55/20 lowest value is 500 what im doing wrong :normal:
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