T value of spring rates?

Please can someone explain the T value on spring rates
for example spec-r springs T7.0 / 2.5
I've read for lbs/in you can multiple the C value (2.5) * 5.71 to get lbs/inch, but what is the T value(number of turns)?It appears the smaller the T value the harder the spring.

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Try to count how many round of the spring, it may be means the length.

nt12011 發表於 2012-6-18 11:25

                               
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Try to count how many round of the spring, it may be means the length.

yes, thats the only thing i can think it relates to (number of turns/coils).
If you look at the 3 racing springs - they only give T value.

                               
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seems rather odd, as its difficult to then know the lbs/in value of the spring, given the T value will also be dependent on the length of the spring.