Z1 makes em as you stated theyre about half the weight as the factory one, also as mentioned previously light weight wheels and 2 piece rotors you will see the biggest improvement there. I forget the rule of thumb but i think its something like for every 1lbs of unsprung weight you take off is equivalent to 5hp? Look it up though! Other than that if shes a daily i wouldnt touch the interior to much.

 

the one ive always heard the most is every extra 100 pounds is equal to 1/10th of a second loss in the quarter mile

 

Weight is a force. The simple formula to calculate the centrifugal force induced by a spinning object is Fc= mv^2/r. Increase the mass, increase the force. Go faster, increase the force exponentially. The faster they spin, the more they affect the handling, and effectively, the more they weigh. And it is not linear, it is exponential.

In short.. unsprung weight makes a HUGE difference.

 

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