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- 2021 Ford Bronco Base
- Your Bronco Model
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- #16
as for the math and measurements;I think the best way to do this is:
- Drive on the highway at three different speeds like 55, 65, and 75 and use a GPS to see what actual speed is (for purposes of example here, lets say it is 61, 71, and 82)
- Calculate the ratio of those three readings (in this case: 1.109, 1.0923, and 1.0933)
- Take the average of those three ratios (in this case: 1.0982)
- Whatever value is in the as-built FORscan, multiply it by the average of the ratios (1.0982)
That should give you a really close result
285 /70 R17
32.7 inches x 3.14 = 102.68
102.68 inches x 25.4 = 2608.072 mm
With that circumference I get -3mph on the dash compared to GPS at speeds of 25, 35, 45. At 65, 70 and 75 I see a -5 mph on the dash compared to a GPS.
I have lowered it to 2525mm and will post what the numbers I get later today.
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