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Old 02-15-2024, 10:33 AM   #33 (permalink)
aerohead
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' lighter wheels '

Quote:
Originally Posted by Phase View Post
I’d be getting ecopias. Idk what they come with but def would do low rolling resistance tires

Lighter wheels in city means less unsprung weight
If you weren't driving a hybrid, I'd say, 'go for it,' however, if you do it, you could inadvertently shoot yourself in the foot:
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1) As has already been discussed, the tire circumference remains the same regardless of wheel diameter. There's no difference in the tread's surface velocity-related hysteresis effects.
2) Since the dual-motor, 13.6-kWh plug-in is already 356-pounds heavier than the 'base' Prius, you're sweating some difference in polar-moment-of-inertia between the two different wheel/tire sizes, in comparison to an 11% increase in all-up mass.
3) Volvo proved that a 'heavier' hybrid can be 'better' than a lighter one, because of the regen phenomena, as, in the case of the PRIME, your getting 81.1% of the energy of 'braking' from an 11% 'heavier car.
4) You'd have to do a complete energy balance on the car to prove to yourself that you wouldn't just be p---ing away good money on an investment that might reward you with a 'zero' return on investment ( 'experience is a cruel teacher....gives the exam first, then the lesson' ).
5) The wheelhouses and wheels 'DO' add around 50% aero drag to a car.
6) And the 'exposed' portion below the belly constitutes about 80% of 'wheel drag.'
7) 'Windage/ Ventilation' drag has been reported at 'nothing' at 'low-speed', to 3% at 141-mph ( 227-km/h ) [ Tesla Model 3 in Germany, by Rob Palin ( aerodynamicist for Tesla Motors )].
8) If your car comes with the 'larger' wheels, something just beyond 'janky zipped-tied cardboard wheel covers' might be all you need to 'erase' the ventilation drag.
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