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Old 06-29-2013, 11:21 AM   #212 (permalink)
Burning oil to move air.
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ausiasmobil - '06 Seat Leon 1.9 TDI Reference
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Originally Posted by echo-francis View Post
to remove some rotational mass and save $$$ on swaping tires 2 times a year I bought 4 kosei k1 ts. they weight only 9.4 lbs.
It would be interesting to assess the moment of inertia of the old tire+wheel and the new ones.
Because steel wheels seems a kind of disk because of its mass distribution.
And the new ones seems like a ring with some rods, so in acceleration and braking maybe it will be any differences even if the weight half the steel ones. (alloys's moment of inertia tending to two times that of a disk).
And we need to add the fuel wasting of aerodynamics because of turbulences, not present in smooth hubcaps. And maybe adding front surface (tires have high pressure contribution, being worst than flat surface) because or adding width.
We also need to think that moment of inertia, being equal de mass and its distribution, dependens on the sqare of radius.
So going from 14" to 15" will increase moment of inertia to (15/14)^2= 115% or +15% worst braking/accelerating.
The suspension will work fine but maybe the lower profile tires will result in non confortable ride.

I'm interested in your results with this new setup.


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