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Discussion Starter #1
As much as I don't want to admit this I will anyways.

I was watching "High rev tuners" on SPEED and there was a commercial or parts spotlight thing (I can't remember now) that said APC is making titanium springs to use on coilovers. Here is a link:http://www.jcwhitney.com/webapp/wcs...gId=10102&langId=-1&AID=1147969&storeId=10101
I went to APCs' website and I didn't see any more info. That site above is retailing them for a few cars and seem to be a very cheap price ($180 for a set), I have no idea of what kind of quality they are but I would definately be interested. Titanium is cool:D

p.s. How much does a stock steel spring weigh? They are saying 60% lighter, just wondering theoretically how much weight we could save.
 

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Wouldn't the coilover be sprung weight? :)
 

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Discussion Starter #3
If you want to get technical, yes the shock body would be "sprung" but the rod and piston would not. And if you really want to get specific I guess 50% of the spring would be too.:p

As for me sprung/unsprung I don't care as long as it's lighter.
:cool:
 

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I just received some new springs from the Exige - they probably weigh 3-4lbs. A big source of unsprung weight for the Exige is the brake rotors and the OEM wheels.
 

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Discussion Starter #5
meat said:
I just received some new springs from the Exige - they probably weigh 3-4lbs.
Thanks for the info meat, that's farely light already. Would you mind giving some more specifics like diameter and number of coils and the spring rate of stock vs. your the new springs if they are different.

And to save you math time, let's say they are 3.5 lbs X 4=14lbs minus the 60% they are quoting is a savings of 5.6lbs:D
 

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Only a small fraction of the spring is "unsprung weight". You determine how much an item contributes to unsprung weight by figuring how much the item moves up and down compared to the wheel when the suspension moves. The ratio of the item's movement to the wheel's movement is the fraction of the item's weight that is unsprung.

The top of the spring is attached to the chassis, so it doesn't move at all when the suspension moves. If the bottom of the spring were mounted all the way out at the end of the control arm, then it would move as much as the wheel and half the spring's weight would be unsprung. However, on most cars, the lower end of the spring is attached to the LCA somewhere inboard of the wheel, so the fraction of the spring's weight that is unsprung is less than half.
 

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You will get a lot more impact working with the wheels, rotors, the A arms, and the hubs, in that order (I'd need to weigh the hubs vs. the A arms but I'm pretty sure the A arms are heavier in the current Elise)...

Roy
 

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A fellow Exige owner just received 2 piece AP Racing rotors (he has the Motorsport brake package) and he said the weight savings is significant. He is going to weigh them and get back to me with the savings.

Tpup - did you ever weigh your wheels to see how much lighter they are than stock?
 
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