Quote: I believe what you're seeing is exhaust valve rotators, tipicaLLY USED ON TRUCK AND rv ENGINES.
tHE SPRINGS ARE ALL THE SAME.
The springs are not all the same. The exhaust springs with rotators are a different size and have pressure differences.
I stand corrected, I think the exhaust springs have slightly shorter installed height because the rotators are thicker.
I not familer with magnum heads like the OP has. I have rebuilt 2 360s that had them in a RV and a hd work van. This was in the early 80s and my memory is not crystal clear. I installed RV cams in both engines and used the springs that came with the cams and both motors ran for more than 10 years after. A small RV cam don't have enough lift to cause coil bind using the rotators with all the same springs on the motors I rebuilt. I drove one for over 100K miles after my boss drove the van for 200K miles before I got it with fresh heads and a RV cam.
