Im not sure
What exactly do they do?
My 1600 has lowered kingsprings/sits pretty low, should I get these? what advantages/disadvantages etc
thay lower your lca's to combat bump steer that lowered datsuns experience once the lca's go horizontal
I'm not sure that is actually true.
The spacers I have seen are Front Roll centre modifiers, i.e raise the front instant roll centre, which compensates for the flattened LCA when lowering.
My understanding of bump steer is that the difference in travel path of the strut and steering system causes the wheels to change toe throughout the travel range (in jounce or droop).
As the outer LCA ball joint to steering arm displacement has not been altered it shouldn't change the bump steer properties (the ball joint still attaches directly to the steering arm, which is then spaced from the strut tube/spindle).
In some cases however the resulting toe change over the full travel range is not linear (Can look parabolic), so thinking out loud, the spacer could change the location of your datum (i.e 0 point) along the parabolic curve which would then have an impact on the overall toe change through the range of suspension travel (maybe)?
Or have I just proved that they are in fact bump steer spacers? my head hurts now, hehe.
Bryan