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Old 02-24-2010, 04:46 AM   #1
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Default Underweight car? been thinking....

If you had an underweight car, what would be the outcome of using heavier wheels?...

Im just curious and thinking outside of the box here!
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Old 02-24-2010, 05:02 AM   #2
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Heavier wheels would increase the inertia in the unsprung portion of your suspension, making it more difficult for the dampers to control the movement of the wheel as it moves over a bump. You are much better off adding the weight to the chassis rather than the wheels.
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Old 02-24-2010, 05:04 AM   #3
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Thanks Quiet day at work with too much thinking!
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Old 02-24-2010, 05:36 AM   #4
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Not to mention the angular momentum which would make it really difficult to turn those wheels to go around corners once they get up to speed. Not a good idea at all.
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Old 02-24-2010, 09:31 AM   #5
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bit of info here on sprung/unsprung weight advantages/disadvantages

http://en.wikipedia.org/wiki/Unsprung_mass
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Old 02-24-2010, 12:55 PM   #6
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Not to mention the slower acceleration and longer braking distance due to the increased rotating mass to be accelerated and decelerated. Large rotating weights can be a bigger enemy to fast lap times than having too high a static weight in the car.

Maybe the biggest clue to this not being your best plan is that there is not a single full-size race car that uses wheels any heavier than they need to be. HTH
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Old 02-24-2010, 01:07 PM   #7
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All great answers, thanks

It was merely one of those "what if" moments I thought about....
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Old 02-24-2010, 01:18 PM   #8
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But if you had say a great bit of torque to spare.... you would have a faster straight away speed and wouldnt it be faster from a rolling start? But it's alll about the unsprung weight deal again. Less weight on drivetrain is always better.
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Old 02-24-2010, 01:50 PM   #9
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Quote:
Originally Posted by vr6cj View Post
But if you had say a great bit of torque to spare.... you would have a faster straight away speed and wouldnt it be faster from a rolling start? But it's alll about the unsprung weight deal again. Less weight on drivetrain is always better.
more rotating mass = harder to start, harder to stop. You should have the same top speed, but it would take you longer to get there...
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