I have been reading the AAEN clutch tuning book and am a little confused. He says that there are really 3 properties to a spring. Engagement load, full shift load and rate. I understand the first 2 and that is the way any manufacturer lists them. You never see the rate of the spring listed (except in his book). From what I understand the rate plays a role in the shift curve also. Is it not as important and that is why you don't see it listed? Is there a relation between the full shift load and the rate? Is there a way to figure out the rate based on the other two properties? Any insight to this would be appreciated. Thanks.