Quote:
Originally Posted by Tambohamilton
fe1rx, firstly a massive thank you for sharing so much of your hard work with us! I'm using your data to create a CAD model of my E91 suspension - I don't have the time, facilities, tools or even patience to get all these measurements myself, and your work is clearly so much better than mine could be.
Not meaning to look a gift horse in the mouth, I think I've found an error somewhere in your front suspension measurements:
Firstly, entering the coordinates for the front upright/strut into cad, I find that the angle between the strut and the hub flange is actually 8.38deg. I've gone through the coordinates multiple times, but can't find my error.
Inserting this component into an assembly with the front arms and chassis pickup points, along with the -3deg of camber, I find that the top strut point is some 21.25mm shy of the chassis coordinate in that location. The strut top point is nearly vertically below the chassis point; I aligned the plane of the front axle/strut with the chassis point, so that the strut/hub was constrained from rotating. I get 6.95deg caster. These measurements assume 0deg toe, though that can't account for all the discrepancy.
I'm sure the issue is just a typo somewhere, otherwise the diagrams you've posted would look significantly different, but I thought I should share at least this part of my findings in case it helps you or anyone else fix an error. 
EDIT: I think the error is in the strut top coordinate, in the hub/strut model; I think this should be 0.0, 222.1, 4 42.5 instead of 0.0, 222.1, 4 22.5.
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Good catch! You are right, the strut top at ride height should be 442.5. Those balloons with the dimensions were populated manually so it as a typo. Thankfully when I entered the dimensions into SusProg3D I got them correct.
I really appreciate your double checking my work though.