Thanks for the feedback.
By perfect I am talking about the relationship between a shock and the spring. The springs going to do its own thing so I am just trying to figure out where the shock would sit in it's travel ideally when the car is just sitting still. i.e it's sag under the weight of the vehicle. I just assumed that if the factory shocks sit at say 30% through their travel then the aftermarket ones would ideally sit at the same amount.
I've included the topping out length in my calculations and made a ratio comparing how the percentage of the aftermarket shock is to the new spring max length, to the percentage of the factory shock to max length of the new spring. I.e 1:1 would be the same ratio as factory, 1+:1 would be too long for spring, 1-:1 would be too small. Hope I've explained that right!??
For bottom out length I've as assumed that there will be a bump stop appropriate to the min shock length.
Ive tried calculating the factory sag but need to knowbhow much weight is on the back to calculate it accurately. The dump sounds like a great idea, might head there this week and see if they would tell me.
I'm waiting on parts to arrive but I think that I will measure and report back everything when I put them in. Should be able to help me verify some of the information.
As for springs falling out, I might add a column checking if the increase is shock length does not increase enough to allow the spring to get to maximum length. Once I know the how much more length the spring has past the max shock length it should be easy.
Do you know of any resources where I can double check my specifications for the springs?