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-   -   Eibach vs Stock free length (https://rennlist.com/forums/928-forum/595907-eibach-vs-stock-free-length.html)

ammonman 10-11-2010 11:38 PM

Eibach vs Stock free length
 
Took my stock springs and Bilstein's out of the front this weekend and broke them down to send the shocks to Bilstein for reconditioning before I install the new Eibach's from the group buy. Today I pulled the Eibach's out of the box to compare the diameters, etc. and noticed that the stock springs are around 13.25 inches free length (close to the factory free length of 340mm) but the Eibachs are only 10.5 inches free length (266 mm.) I know the Eibach's are a progressive spring with a slightly larger wire diameter (.615 vs .570) but are they actually supposed to be that much shorter?

Mike

GlenL 10-12-2010 01:02 AM

Yes, Shorter and stiffer to give a similar ride height. If they had the same length and were stiffer then your car would be too high.

ammonman 10-12-2010 07:18 AM

Understood about the necessary difference in height. I was just surprised the difference would be so great.

MIke

puyi 10-12-2010 07:51 AM

The aibach spring are 2 times stiffer than the stock. So if you consider stock springs and a weight of 300 Kg on it, they stick by 100 mm, as the eibachs should stick by 50 mm only. So from the free lengt of 340mm, the stock springs will be compressed and L1 = 240 mm. The eibachs L1 would be 230 mm. Gain = 10 mm BUT, bilstein gas shokcs are known to be pre loaded and raise the car by 10 mm.....230 +10 = 240.
CQFD!

Stephane


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