74 1.8L rear coil spring color dots Options

[L-Jet914]

I am swapping out my original rear coil springs for new 100lb springs from 914 rubber. I was reading through the factory service manual and found out that my springs are from the Group 2 and Group 3 stiffness via the 2 and 3 green dots on the coil. The service manual states there are 3 different stiffness options. I wonder if all the 74 1.8s came with this spring option or if it varied. Per the service manual it says they were suppossed to be matched in pairs but from the factory I have no idea haha. @starbear @wonkipop

[davep]

The springs were manufactured to a common specification, then tested for separation into the three groups. This reduced the left to right difference in production for a better balanced car. If one spring had to be replaced then it needed a replacement with the same # of dots. Over time the springs weaken and sag. A worn out spring will appear bowed since it is not strong enough to keep its shape. I would expect that all original springs are well past their expiry date by now except those that are NOS.
I am not sure what the ideal spring rate (or length) is for a typical street driven car, nor for a performance car. However, one would need to dial in a car to get it to sit evenly (left to right, and front to rear) and this would imply adjustability with the rears. Different perch heights or threaded perch capability for the ultimate adjustability.

[L-Jet914]

The springs were manufactured to a common specification, then tested for separation into the three groups. This reduced the left to right difference in production for a better balanced car. If one spring had to be replaced then it needed a replacement with the same # of dots. Over time the springs weaken and sag. A worn out spring will appear bowed since it is not strong enough to keep its shape. I would expect that all original springs are well past their expiry date by now except those that are NOS.
I am not sure what the ideal spring rate (or length) is for a typical street driven car, nor for a performance car. However, one would need to dial in a car to get it to sit evenly (left to right, and front to rear) and this would imply adjustability with the rears. Different perch heights or threaded perch capability for the ultimate adjustability.

Dave,
Thank you for your input on the subject. More information to add to my memory banks.