I have two new sets of valve springs and one used set. Each set has a different color paint on them. One set blue, one set cream and the used set red. Are they painted as a matched set or do they vary in rate? I do have a spring tester available an hour away and may compare them sometime. Just wondering if anyone has a answer for this?
I don’t know if this helps, but S3 XJ6 springs have a blue stripe. I should have other springs I can check. I know I have a new in the box set of V12 springs at the shop.
The one new set had BL box yet and by part number fits all xk 6 cylinder engines. Those are the blue set. The red came out of a 3.8 head.
The cream are new but out of original packing and came with a disassembled 3.8.
You don’t need fancy fixtures to do spring calcs. See sketch.
-
Measure the unloaded length of the spring. This is Xo.
-
Place spring under midpoint of the bar.
-
Hang known weight (W) from end of bar.
-
Measure the compressed length of the spring. This is Xf.
-
We can calculate the static resistance of spring, F, from Fl = W2l, therefore F = 2W
-
The spring rate is equal to F/(Xo - Xf)
2 Likes
Thanks! I have an actual spring measuring tool available to my use. Just curious if the color meant anything.
