i feel the two go hand in hand in that as you roll toward more negative camber you also get toe in.Is the toe setting affected by the negative camber gain that occurs when the rear suspension is loaded?
A very accurate model can be made measuring by hand, and compliance can also be figured as well. It'll just take more time, and patience.Finally this is going somewhere and I would like to compliment your work but I think that you are getting to the conclusion that this is a snow ball effect and everyday more variable will need to be accounted for like the next subject would be suspension compliance. I know that it looks good to see all the numbers in front of you but are those truly the dimensions that we are dealing with in the real world. There is a lot more to this than just measuring values with hand tools and alignment machines. It is ok for marketing and demonstration purposes but there is too much room for error to use these values as the base of you research. Remember the famous school quote, garbage in garbage out. To accurately solve this problem you would need to scan the entire suspension to locate pivot points then take the car to a place like Morse Measurement (www.morsemeasurement.com) to compensate for all the compliance on the suspension components at operating conditions to generate a new corrected x,y,z model to import to a real simulation program like Adams Mitchell or even the Lotus version to plot out suspension travel according to ride height. Then after making the new projections based on your new parts, go back to the tester to validate your work. To finally realize that you might have to make new uprights, control arms and replace the rubber bushings for spherical bearing types which at this point is not cost effective. This is not a secret; in a nutshell this is what real race teams go through every year they just do not make parts for street cars.
That and the change from arm motion isn't linear either. Take a look at the screenshot of the spreadsheet.From what I can see, the dynamic toe change wouldn't be linear because of the compliance of the bushing on the inside end of the link and the ball joint on the outside. This would in my eyes make the snap oversteer not very predictable. Is anyone actually experiencing it?
Were you able to take readings at various suspension heights? It would be useful to know the actual amount of toe change.Additionally, it was noticed by our guy we use for alignment as his setup is one that can load the suspension and take measurements.
I suspect you are right on this. I have yet to experience the snap oversteer with the KW's, except for power oversteer at low speeds, which has always been there with subarus.That and the change from arm motion isn't linear either. Take a look at the screenshot of the spreadsheet.
On the snap oversteer - lots of folks are seeing it, us included. Now, the question is - is the snap oversteer due more to the toe change or due more to bottoming out the suspension travel since it's so short. I have a feeling it's more a suspension travel issue, but we need to set up some tests to be sure.
I've got it roughly calculated, but I want to set up a toe board and dial gauges and just do a real world measurement first.Were you able to take readings at various suspension heights? It would be useful to know the actual amount of toe change.