Thread: Prius 75-91mpg
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Old 05-03-2019, 08:18 PM   #28 (permalink)
Nathan jones
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Originally Posted by Ecky View Post
Unfortunately I think this may undermine what you're trying to achieve.

By going smaller, you *effectively* make the wheels heavier, because they have to spin at higher RPM for a given road speed. This is normally close to a wash, but by going wider at the same time you're definitely going to cause the wheels to hold more angular momentum, even if they weigh less on a scale.

Most cars would "feel" like they accelerate more quickly with smaller tires, but it would be because they're now geared lower. I don't know if this applies in a Prius.

You would achieve your goal of lowering the car, but you'd also likely hurt both aerodynamics and rolling resistance (all else being equal) with a smaller, wider tire.
Hi yes, the wheels may weigh a very small amount more/equal, yes the gearing is changed and aerodynamics is changed. Lowering the car increases the pressure above and reduces the pressure underneath, helping to hold the car down. Pressure drag is also increased but a small sacrifice for race situations. I dont think over 107mpg is possible with this chassis/engine/surface area

n.b unless the night temps are above 30c and theres no traffic
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