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Old 12-05-2008, 12:04 AM   #8 (permalink)
theunchosen
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Quote:
Originally Posted by DifferentPointofView View Post
yea, unsprung weight deals a toll on the car, much moreso than the spin of the wheels.

Are your tires the same diameter?
?

My tires are. . .old on gotta think. I wanna say 60 MM off the tire for the profile. Its the standard profile size for a 13 inch tire in all aspects.

The 18 inch tires were definitely heavier and taller. The Del Sol sits much lower now because the tires are thicker(taller) but the wheel is much smaller(5 inches in diameter smaller). I think the wheels are 60-65 mm which is less than 3 inches. so its an overall decrease of at least 2 inches wheel diameter and a slight change in weight.

I'm not really sure how the unsprung weight influences the MPG?

I know that not having more air cushion in your tires gives you a really rough ride that can't possibly be good for the car, but I am not sure whow it would affect FE.

It's late and my brain is not functioning. I'm not saying you're wrong, just I can't put it together right now lol.

The uniform motion does create a heavy draw on powerthough because its the moment of intertia for a donut. Spin your car wheel and then spin a bicycle wheel. Your car probably has less friction and should spin faster but doesn't because the inertia of the tire resists the moment applied.
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