If you are able to provide or correct any information on springs, please do so in this thread and I'll try to keep this updated. Also, if you feel other information should be added, please suggest.
If you have side-view photos of your car, preferrably on stock wheels and tires, please post them here and I will add them as well. If you have aftermarket wheel or tire sizes, please post those as well. Again, stock wheels and tires are preferred for comparison.
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Key Information
Advertised Drop: Front/Rear in. (Front/Rear mm)
Advertised Spring Rate: Front/Rear lbs./in. (Front/Rear kgmm)
Linear or Progressive
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OEM
Spring Rates?
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Eibach Pro-Kit
Advertised Drop: 1.6/1.3 (40.6/33.0)
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Eibach Sportline
Advertised Drop: 2.0/1.8 (50.8/45.7)
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H&R Sport
Advertised Drop: 1.6/1.4 (40.6/35.6)
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Progress
Advertised Drop: 1.5/1.3 (38.1/33.0)
(CarDemon)

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Skunk2
Advertised Drop: 1.5/1.0 (38.1/25.4)
Advertised Spring Rates: 175/350
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Spoon
Advertised Drop: 1.5/1.0 (25.4/25.4)
Advertised Spring Rates: 195/291
(macks75)

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Sprint
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Swift
(Jimmy101)

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T1R S-Coil V2
Advertised Drop: 1.6/1.4 (40.6/35.6)
Advertised Spring Rates: 179/342
(aj-racing.com)

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Tanabe DF210
Advertised Drop: 1.8/1.3 (45.7/33.0)
Advertised Spring Rates: 174/274 (3.1/4.9)
()
(jits14)

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Tanabe GF210
Advertised Drop: 1.5/0.9 (38.1/22.9)
Advertised Spring Rates: 190/279 (3.4/5.0)
(bulletproofautomotive.com)
(4dr4life!)

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Tein H.Tech
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Tein S.Tech
Advertised Drop: 1.8/1.2 (46/31)
Advertised Spring Rates: 163/336 (2.9/6.0)
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Vogtland
Advertised Drop: 1.6/1.0 (40.6/25.4)
(RacerDre)

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Zeal X-Coil
Advertised Drop: 1.0/1.2 (25/30)
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