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Old 11-20-2014, 08:50 AM   #5 (permalink)
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Quote:
Originally Posted by BabyDiesel View Post
Old Mech, would not the 764 & 728 need to be switched? Larger tires cover more distance per revolution than smaller tires, adding distance.

(300x764)/728 = 314.84

I believe you would add the 4.95% to the odometer when you fillup, hat_man. That would mean in 300 miles, you have really traveled 314.84 miles. I have had to do this to my car as I went up 3.4% from the original tire size.

Let me know if I have let my sweet tea sugar high write nonsense lol!
Old tires 764
New tires 728

Lower tire revs per mile with the new tires, means fewer signals to the speedometer for every mile travelled. The new tires roll further every revolution, thus the lower speedometer and odometer reading. I think I got it right, but I did go back and check the OPs figures.

To check the odometer with the consistency of your commute, assuming you know the distance of the previous reading, confirm the calculations with the distance of the new reading with the larger tires.

I just got my sweet tea sugar high.

Sometimes it's easier to fudge the factors. If the tires were twice the diameter,the speedo would read half the speed. Increasiing diameter will always reduce the instrument reading.

regards
mech
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