What are these springs

[smutly]

When I bought my Caterham I was handed over a load of spares. Amongst them are 4 springs and 2 Bilstein Dampers. They look like they have had little or no use. Can anyone identify them from the following:

 

2 Black springs with green painted ends (where the spring seats)

7.43” (189mm) lg

1.9” (48mm) ID

2.54” (64.5mm) OD

0.32” (8.1mm) Wire Dia

9 Coils

 

2 Black springs with red painted ends (where the spring seats)

9.5” (241mm) lg

1.93” (49mm) ID

2.64” (67mm) OD

0.36” (9.1mm) Wire Dia

8 Coils

 

Damper Pt No: 6052169M000

 

My present Dampers are completely red and the rears are progressive type but seem quite soft so I thought I might experiment with these but I would like to know what I’m experimenting with!

 

Any help would be much appreciated.

 

 

 

[martyn_heesom]

Have a look at the following websites. http://www.iroczone.com/calcs/chassis.htm has the calculation from the data you have measured. The number of coils in the calculation is the total number minus 1 if the ends are simply ground flat, or minus 2 id they are squared and ground (see http://www.efunda.com/DesignStandards/springs/spring_design.cfm, about half way down the page, for an illustration of this).

 

Martyn

[Chelspeed]

Or just measure it. Put a board on the spring and stand on it. Measure the compressed spring length and then calculate the spring rate (in lb/in) as:

 

(your (plus board) weight in lb's) / (original spring length - compressed spring length).

 

Sounds easier than it is actually, you need to hold onto something to steady yourself and get someone else to measure the compression while you teeter about, when you fall off the spring goes bouncing off across the garage. Actually quite amusing to do, hours of fun for all the family

[Jason Plato]

😬 *thumbup*