Vince - I think you are asking me what the motion ratios are? If so, the fronts are struts so the motion ratio is essentially 1:1. On the rear, I do not know exactly what the ratio is but I believe it to be in the 0.8:1 (spring:wheel) range. I know they have to run stiffer front wheel rate than rear in an attempt to balance the oversteer and one guy in particular was having understeer issues with his Cup car but was more in the "enough money to track a Porsche Cup" category and less in the "know how to tune a track car" category
Were it mine I would have swapped out springs between sessions and solved the problem.
The Nova has two different mounting holes where I can set the ratio at either 1:1 or 0.8:1. So essentially I should be able to get similar motion ratios and the Nova will be a bit heavier - those Porsches are in the 2600 lb range with full fluids IIRC. I know they list as around 2500 lbs from Porsche but believe that may be dry weight. This implies I may need higher rates yet to achieve best results.
I can say that every single time I went up in spring rate in my old track car the car went faster. I was set to increase it again and then decided to sell and do a Nova project instead. I was at
wheel rates higher than many people run in
spring rate. There are two basic schools of thought (and this is a rather serious simplification but at the fundamentals accurate) = use the spring to control the car and the shock to control the spring, or use the shock to add control for the car along with a lower spring rate.
The difference is really the individual's ability to tune. I do not have a team from Penske follow me to the track like Pro teams do to revalve shocks based on track data but I can swap a spring in about 15 minutes per corner
so as long as I don't move too far in spring rate and overcome the rebound control that is valved in it, I will have a similarly good car. In the end, I will never be as fast as having a team of engineers following me around, but I will be as fast as
I can be if I focus more on springs and less on shocks. Basically the engineer at Penske told me he would set me up at near zero compression and let the spring do the work which is exactly what I did on the Porsche with them previously. Having the ability to tune in 0 to around 150 lbs/in equivalent compression is nice to have to predict if I expect to go faster with the next stiffer spring.
To make the discussion more interesting we would get into the characteristics that springs have a linear stiffness that starts at 0 lbs and increasing with translation whereas shocks have a stiffness that is far more dynamic and based on velocity of wheel motion v. total travel. That is where the engineers can come in and balance the overall setup and even tho' I am a degreed mechanic turned degreed mechanical engineer, that stuff is way out of my realm/expertise.