I know that seems to be the impression around here.
Still more than likely, I think I need to push back and say that I doubt everyone is comparing apples to apples. Too many variables from the dynamic tire spring rate to dampener type to target suspension frequency to weight distribution to aero... which to the best of my knowledge... is why the pros start by filling out a weight transfer work sheet.
My theme here is that this is an area that tends to have a lot of depth. I've read about the spec PCA guys that are really serious about their chassis setup doing bumpstop load vs. length and testing them to measure their effective spring rate and figuring that in to their test results. Apparently as I understand it rules limit them to the 996/997 05' - 07' specs and so they throw a ton of shock dyno time at it instead of using such guesswork.
Frankly, I'd say that I feel pretty confident that due to the wide disparity among NSX owners both in terms of driver competency as well as ride setup, traction/go-fast budget, consumer willingness to accept compromises, limited real world quantifiable test data, etc..... that a one size fits all approach touting a specific ratio might not be the best advice going. I'm not saying that your reccomendation given seat of your pants results at Road Atlanta is a bad starting spot, but I don't know that it would work well or scale for everyone.
For example, if you run in a high downforce configuration you are going to want a stiffer rear spring and large O.D. piston that offers equivalent performance but with less piston travel to help keep aerodynamic changes more to a minimum. Even if you think you have it all worked out on a bone stock car... it really doesn't hurt to have a couple sets to experiment with.
That is to say nothing of the spring itself. A quote from Kent Chen with Endless USA:
"Spring rates may just seem like a set of arbitrary fixed numbers, but different brand springs with the same spring rates can actually differ in performance and feel quite a bit.
How so? Different springs use different material and have a different number of coils amongst other things. It's to my knowledge that a spring that reaches a specific spring rate level quicker and with less spring stroke is generally considered to be superior. You do not want to have any unwanted tendencies during expansion and contraction. A spring with a motion characteristic that is smooth and linear with the ability to catch road surface information directly. A spring with accurate levels of response and a smooth yet solid feeling is what you would want to accompany a very specific shock absorber."
Without going too far on the tooth with it... I think that suspension tech is all about details. Simply staggering a set of brand X springs at a pre-determined ratio might get you a little, but I'm pretty sure any of the pros would back me up and say that there is a lot more to it than that.
