marginal toe in does help w/ oversteer, but you can just set a marginal static toe in which will then be maintained throughout suspension travel. There's no need for a toe curve like there is for a camber curve because of body roll. You are comparing this to a solid axle, which is a much less rigid mounting option than a proper designed 5 bar or double a arm suspension (assuming you're using solid bushings and all) The flexing in a solid axle is what causes the brake toe out and the torque to in condition. This does not mean you can apply that to an independant suspension as something that needs to occur. Having said that, not even all live axles give toe in under power, some even toe out, especially those w/ weaker cases. Porsches had a similar problem w/ their semi trailing arms. They had terrible torque steer, something not very common in rwd cars but the semi trailing arm setup is notorious for this because of the arms being mounted on a diagonal axis towards the car centerline. This causes toe in under acceleration and toe out under deceleration 9letting off the gas or braking) because of the loading in the outer bushing and thus allowing deflection. Their solution was the weissach axle, basically splitting the trailing arm w/ a bushing in the front so that under deceleration the rear wheel toes in (especially important on the loaded outside wheel). These are all attempts to create a toe in situation to give understeer as understeer is much easier to control than oversteer.
What i want to illustrate is that you can just set a static toe in and have a suspension that does n ot change the toe so you wil never run into any toe control issues, especially toe out oversteer. However too much toe in is also not desireable. If you have a semi trailing arm suspension that does not use a sectioned arm like the weissach (and a lot of cars use the semi trailing arm) you will see a lot of static toe in being set just to counteract any toe change towards 0 or even out. This is not because more toe in is better but because they want to improve upon the shortcomings of the IRS design.
I agree on lowering the CG. I moved a lot of stuff aroudn on my car and think I lowered the cg quite a bit, my gas tank is about as low as it gets. By lowering the car you lower the CG but also the roll center, a higher roll center will reduce (weight shifting induced) body roll and this will let you run softer springs for a more responsive suspension and smaller sway bars (and thicker bars take away from the independence of the suspension), the only big drawback is that it puts more load into the tires however w/ modern tires in a wider size tat won't be a big problem. Given the same tire it would reduce the scrub angle significantly.
Your outer rod end is most definitely not in the same position as the greenwood one. Take a closer look at the sketched drawing and the picture. They use a chopped off trailing arm. The rod is about mid plane in relation to the spindle. It looks like it's a bit lower
Yours is significantly lower. This is the main reason for the geometry misalighment w/ the halfshaft. I'm willing to bet that the stock eaton type diff has a u joint center in the stub axle that's 8.25" off center or very close to that.
Have you even seen that the drawing depics WHERE to weld the center bracket? 8.25" from the centerline.
Here's a little sketch I made of that later type susp. See where the u joints and pivots line up and are all parallel w/ the driveline axis?
This was the latest version of that greenwood 5 bar system.
The other picture is just an installation drawing, I feel the picture of the real thing is a lot more valuable source of info.
