[68c10airstream]

A few geometry questions, how do you adjust caster and camber? Shims behind upper control arm cross shaft. If so doesn't this effect the center line that is supposed to run through the center of the cross shaft through the inner tie rod end and down through the lower cross shaft to eliminate bumpsteer? I have been curious about the factory bumpsteer values in comparison to this newer style front end. I noticed the bumpsteer gauge being used but no values. I believe the front ends on the market that have adjustable upper control arms that lengthen or shorten as needed for caster and camber would not alter the bumpsteer values. Anybody ever dig into scrub radius, what backspacing in conjunction with wheel diameter to yield a certain scrub radius value? In the early 80's as a subaru mechanic, the factory advertised zero scrub radius. This was the center of the footprint at the pavement was exactly where the SAI (steering axis inclination) imaginary centerline through the ball joints ran down to the pavement and contacted at exactly the same point as the center of the contact patch of the tire. Our dealership installed aftermarket wheel that were dished outward ( wider track width) and we battled with steering wheel shake, sensitive steering, etc. Reinstalled factory wheels and all problems gone. Obviously manual steering on this application.