[tiderfish]

Greetings, I have changed the rims of my ZX2. I know the new tires are slightly less in diameter. They are from a 2004 Miata. I want to know how to adjust my mileage to account for the faster tires. Here are the stats:


Stock Tire - 185/60R15
Section Width: 7.28 in 185 mm
Rim Diameter: 15 in 381 mm
Rim Width Range: 5 - 6.5 in
Overall Diameter: 23.74 in 602.99 mm
Sidewall Height: 4.37 in 110.99 mm
Radius: 11.87 in 301.49 mm
Circumference: 74.58 in 1894.3 mm
Revs per Mile: 876.1
Actual Speed: 60 mph 100 km/h

NEW Tire - 205/50R16
Section Width: 8.07 in 205 mm
Rim Diameter: 16 in 406.4 mm
Rim Width Range: 5.5 - 7.5 in
Overall Diameter: 24.07 in 611.37 mm
Sidewall Height: 4.03 in 102.36 mm
Radius: 12.03 in 305.56 mm
Circumference: 75.61 in 1920.4 mm
Revs per Mile: 864.1
Speedometer1: 59.1 mph 98.6 km/h

Speedometer Difference: - Speedometer Difference: 1.388% too slow
Diameter Difference: - Diameter Difference: 1.38%

So do I just divide miles traveled by 1.388%

My last tank was 294.7 miles. When I divide that by 1.388, I get 212miles. That seems way too low.

Any thoughts?