Determining SpringRates on GC

Crim · 01-31-2004, 10:06 AM

Anyone know how to determine spring rates from GC springs?

The numbers are listed:700.250.300
180.64.44

chris13bsr20 · 01-31-2004, 04:30 PM

Its supposed to be like this:
700 = 7 inch length
250 = 2.5" ID
300 = lb/inch (your rate)

I dont know what the other #'s mean.

reds13 · 01-31-2004, 05:14 PM

Quote:

Originally Posted by chris13bsr20

Its supposed to be like this:
700 = 7 inch length
250 = 2.5" ID
300 = lb/inch (your rate)

I dont know what the other #'s mean.

I think they are metric.

Crim · 01-31-2004, 07:13 PM

hrm well I was supposed to get 300 in the front and 250 in the rear...

So I wonder how the rears are computed...

chris13bsr20 · 02-01-2004, 08:05 AM

This is how Eibach stamps and rates their ERS springs. Its the same for all of them.

MEclassic · 02-01-2004, 02:26 PM

180 mm / 2.54 = 7.08"
64mm / 2.54 = 2.52"
44 n/mm * 5.588 = 245 lb/in

Your springs are 7", 2.5" i.d., 250 lb/in, just in metric measurements. Rounding accouts for the slight variation in calculated english units.

chris13bsr20 · 02-01-2004, 03:41 PM

Why do they put the 700.250.300 on there? I read on the Eibach website that those #'s determined the length, ID, and rate?

MEclassic · 02-01-2004, 04:47 PM

I think the first set of numbers was printed on his front springs, and the second set on his rear springs. Eibach probably makes them with either English or Metric markings, they are a German company, right? I imagine GC just happened to have a pair with metric markings in stock when he made his order.

Josh

Crim · 02-01-2004, 05:21 PM

cool, I definatly appreciate it! Now I can decode my Z's spring rates too..