Technical Suspension - spring rates

[robinsonx19]

Hi, Can anyone confirm the compression rates or the following specs for either standard or lowered springs for a 1500 X1/9. The information I have suggests FAZA series 1 lowers (which I think are from the US) have the following specs.

Rears:

Free height 10.25" (260mm)
Car lowered by 1/2" (12.7mm)
Length under static load on car of 235kg (518lb) = 187mm (7.4")
Coils - 8
Compression rate 154lbs/inch (27.6kg/cm)
Spring wire diameter = 12.7mm (1/2")
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Fronts:

Free height 9" (229mm)
Car lowered by 1" (25.4mm)
Length under static load on car of 200kg (440lb) = 145mm (5.7")
Coils - 8
Compression rate 117.5lbs/inch (21.0kg/cm)
Spring wire diameter = 11.8mm (15/32")

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