If the road or track is cambered by say 2 degs to the inside, that can be factored into the equation. Either drive through it real slow, or stop every few feet, take measurements, then either factor it in.... or simply use the 'zero out' feature. Ok, say it is a consistent 2 degs..and we then zero the reading out. Take the corner at speed, and at 1G, it should read aprx + 2.0 degs. Or don't zero it out, then it should indicate...0.0 degs. Moot point really.
My point was that if you're looking at the car's orientation against an imagined true vertical, 2° true roll because the road is cambering 2° out from underneath the inside will look like 0°. Tends to be misleading if you're not paying attention to the actual ground contour.
Norm, your calcs / software/ analysis may be on track / correct, but it still does not explain the effect that both myself and jj427r are seeing. This is not some subtle difference either, blatantly obvious that something somewhere has changed.
Perceptions can be misleading. I'm not trying to claim the you and JJ aren't noticing anything, only that you're not assigning crediting where it belongs.
"I suspect that any increase in stiffness (esp torsional) may well enhance the effect of the front sway bar."
Norm, your comments above is what I was alluding to. With the jacking rails installed, and say taking a sharp left hander, the front sway bar now has the entire left side of the car to contend with....and not just the left front portion.
No. Increasing chassis stiffness does not change the front sta-bar from being responsible only for your left front corner to the whole left side. But for it to suddenly take over the entire left side's load transfer that's resisted by the bars, you'd have to disconnect the rear bar. And then you'd be seeing more roll rather than less.
In actuality, the front bar is only providing one of the resistances to body roll, and the way load distribution works is that it divides up according to the relative stiffnesses. It's a springs in series/springs in parallel situation, where the stiffness of a reasonably stiff chassis plays only a minor role.
In my case, the front ends of each steeda jacking rail has a flat plate welded to it, with the flat plate facing inboard....(90 degs to the 2" x 1" CM jacking rails)
I really don't want to get into finding areas and torsional resistances when the S197's basic chassis really doesn't leave much flexibility for them to help resist. Compared to the existing S197 main structure, these are small elements in a secondary structural role.
The stiffness that they do add is far more effective at changing structural vibrations, which is something that does lead itself to being felt. It should make sense that a car that feels more solid is one you trust better and are more readily willing to drive harder.
Point here is, in my case, with the recent addition of the pair of steeda jacking rails, it's now one continuous brace...from eng cross brace... straight back to the front end... of each rear LCA mount.
It takes more than the simple fact that they're present. It's how much additional stiffness they provide compared to the basic S197 chassis stiffness that really matters. It's the numbers that matter here, not the words.
The addition of the CM jacking rails appears to be the final missing piece of the puzzle.... now tying the rigid front end....to the rigid back end of the car. The entire affair is pretty damned rigid. You folks can call it placebo effect, confirmation bias, pseudo junk science, or anything else you care to. [/QUOTE]
Stop. Just stop. I'm trying to teach something that I think I'm still reasonably qualified to talk about.
I'm sorry if I can't seem to find the approach that would really make this structural and mechanical engineering stuff 'click' for you. But if I didn't have a pretty firm grasp of the concepts myself, I wouldn't have been able to make an engineering career using them that spanned 42 years.
I am not among those who might be calling this a placebo effect or anything subject to confirmation bias. I'm looking at this in a strictly objective manner as far as the structural and mechanical effects are concerned. And I know a little about what makes for a more confident driver, or conversely that a driver whose car provides a less secure subjective feeling just isn't going to drive it quite as hard. It may not take much to go from less secure to more so.
Norm