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Front suspensions tend to have isolated/bushed control arm/strut mountings at the frame so that the physical suspension has compliance. Steering linkages tend to utilize ball joints with substantially less compliance than bushed joints. Even in a FWD car, the tractive loads will pull the mounting arms forward but the steering linkages will be unaffected, potentially causing toe-out. I wouldn't agree with a blanket statement that FWD cars run static toe-out; it does not seem logical. Quite possibly nominally less toe-in than RWD, but rarely to never static toe-out.
A vehicle with a dynamic toe of zero can still track straight and find the steering center with the right combination of caster, trail, kingpin inclination, and scrub radius (all of which are relatively independent). Usually, but not always, the line of caster passes through the rotational center of the wheel, making caster angle and trail co-dependent. If the line of caster is offset from wheel center this is not the case. Likewise, kingpin inclination and scrub radius (distance between center of contact patch and the ground intersection of the line passing through the upper and lower wheel-end pivots in front view) are co-dependent only for a given wheel offset. Changing wheel offset changes scrub radius independent of KPI.
Running more positive caster helps steering return to center, but increases steering effort and jacking (lifting) when turning, as does high kingpin inclination. Running a zero scrub radius reduces turning effort but would make center feel more numb and a bit squirrely (tire will still only "scrub" when turning, not going straight). Running a negative scrub radius (KPI line intersects tire CL above ground) will cause dynamic toe-out under power (reverse under braking) with FWD. Positive scrub radius will cause dynamic toe-in under power with FWD, and will cause centering under power. Running non-zero scrub radius with FWD would likely make for some horrendous torque steer.
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