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Subject Empirical data > Theory.
     
Posted by Antihero on October 17, 2012 at 9:13 AM
  This message has been viewed 398 times.
     
In Reply To Unsprung weight posted by ZiNnYc on October 17, 2012 at 08:07 AM
     
Message [ http://www.modified.com/tech/modp-0906-performance-wheel-test/viewall.html ]

If you can't measure the negative impact of +3.4 pounds per corner unsprung weight between an ultra light weight wheel like a $4000 Rays CE 30 @ 17.4 pounds and a $1200 FN01 RC at 20.8 on a race track with proper timing equipment, same car, same brand brand new tires, you certainly certainly won't notice 1-2 pounds per wheel on the street. It may even "feel" different, but it doesn't perform significantly better.


To clarify my backpack statement:

[ http://hpwizard.com/rotational-inertia.html ]
18 pounds @ 11.799
21 pounds @ 13.766
difference of 1.967 kg per wheel of "equivalent mass"

1.967 x 4 converted to pounds is 17.34596 of "equivalent mass"
Actual weight added was 12 pounds.

Adding three pounds per corner is, according to a guy who believes in unsprung weight is serious business and has put a lot of thought into the theory is like adding less than 18 pounds of static weight. 18 pounds on a 3500 pound street car is completely irrelevant.

NOTE: I am completely excluding boat anchors from my argument. Cheap/19"/etc 30 pound wheels are junk and I don't think anyone buying them cares about performance anyway.

Antihero



Putting AMS garbage, and $500 ebay wheels on a Z is like
dressing a Victorias Secret model in a Walmart dress and
Payless shoes. You're embarrassing yourself.

     
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