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Old 01-08-2021, 11:02 PM   #2 (permalink)
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ND Miata - '15 Mazda MX-5 Special Package
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Some back of the envelope math suggests the rotational inertia of your wheels is around 6.5% of your total vehicle's inertia (I made what I felt were some reasonable assumptions about wheel moment of inertia). The wheels themselves are also, surprisingly, just about 6.5% of the total vehicle mass, so you're looking at affecting approximately 13% of the energy need to accelerate and decelerate. Or, in other words, my math supports that taking a pound out of the wheels is like taking two pounds out of the car.

Looks like the total inertial savings is ballpark 1.5% from the entire vehicle. I can only guess at how that would relate to fuel consumption. Maybe 1/3 to half that in mixed driving?
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