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Old 01-14-2010, 08:37 PM   #30 (permalink)
cfg83
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RobertSmalls -

Quote:
Originally Posted by RobertSmalls View Post
...

Having read about those >1lb brakes (rotors, presumably), I couldn't resist running a calculation. Assume your brakes need to be able to do a panic stop from top speed on a warm day without boiling your brake fluid. Assume that the top speed of the Very Light Car is 75mph, and that its braking system has a thermal mass of 2kg and the same specific heat as cast iron. Thus the mass of the vehicle, its occupants, and its cargo is not more than 315lb.

Uh huh.

Maybe they have aluminium brake rotors with cast iron linings, and a 630lb car?
Thanks for doing this calc. 315 lbs sounds fantastical without using exotic materials like carbon fiber, which they don't want to do. When I was looking at the test mule, I was thinking kit-car tubular chassis. It looks like a dune-buggy.

They claim their brake rotors are 1/5 the weight of a regular car. My car weighs 2400 lbs. From my simplistic POV, 2400 / 5 = 480 lbs. Their mule only has one person driving it, so I will assume only one passenger. The average weight of an American Male is 191 lbs. That's 671 lbs.

Does that look similar to your numbers?

CarloSW2
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Last edited by cfg83; 01-17-2010 at 04:30 AM..
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