It’s time to finalize my parts order, which means I have to pick all the rod ends and spherical bearings for the suspension. Up to now I’ve relied on rules of thumb, which isn’t good enough for a state-of-the-art race car. So I simply opened up one of my higher-level chassis models in Solidworks, one with most of the suspension attached, and created a 3D sketch of the upper and lower left front suspension A-arms, constraining the endpoints of the lines to the centers of the rod ends and spherical bearings. Then another line to simulate the upright and tire, and I’m done with the sketch. Then I created a structural member along each line and opened a static simulation study. In the study I constrained the inboard ends of the A-arms to zero translation and applied a 1400 pound load toward the rear of the car to simulate 4-G braking. Run the study, and voila! axial loads on each member.