The cornering i'm not as concerned about but i do want straight tracking and not feeling "dicey" when i'm up around 75-85mph. (being a daily driver, i'm not canyon carving with a 4 door but i do drive some highway.) I felt like i read negative camber was noticing the car jumping to the side some at highway speeds when hitting bumps or whatnot? I definitely get that now, and some of the "knife's edge" feel at around 75mph.
Would better directions to them be more in line with:
Caster: Around 3.5 positive total (Drivers 1.5 - Pass 2.0)
Camber: +.5, (.350 each side)
Steering axis inclination: +3.5 to +4.5
The inclination i got off of the linked PDF, do you even give them that or do aligning the caster/camber/toe result in the correct steering axis? I've never asked for specifics there. I don't want to give them un-obtainable numbers or something that is like "Well yeah, if you gave me these that MEANS this" and look like a moron.
Only toe-in is total. Do not add caster or camber to get a total. I.e. your caster should be 3.5 degrees on passenger side, 3.25 degrees on driver side.
Steering axis inclination is built in to the way the spindle is manufactured. This is the angle of a line drawn through the ball joints when viewing from the front of the car. It is 3.5 degrees on a 55-57 car, inboard at the top. Some alignment machines give you a steering axis inclination on the printout. It is simply the algebraic sum of camber and inclination angle. As an example, with +1 camber, your inclination angle would be (-3.5 + 1) = -2.5 degrees. I personally think this is misleading and confusing. The spindle is not going to change unless it gets bent in a wreck. Camber is a direct measurement that affects the tire patch on the road.
If you are worried about camber making your car "dart around" have them set it at zero.
But more important, positive caster is what makes the car track straight and true, not camber. It also helps in restoring the steering to straight ahead when exiting a turn.
Last thing, you can't get 3.5 degrees positive caster with a totally stock front end. Maybe +1 degree, some cars less. You need aftermarket upper control arms, offset upper control arm shafts, or modifications to the upper control arm mounting brackets to get more.
OK, thanks for that correction! I do have aftermarket uppers and am close to 3.5 now, but i need a re-alignment after a pitman arm swap (new pitman arm is slightly different center, about 1/4 turn off steering wheel now), lowering the car some with the coil cut, and they read my notes wrong last time and did camber negative (i wrote ~.5 camber, meaning around .5...they took it as negative .5)
I could just correct the steering wheel being off, but i don't know how much if any lowering changed anything and i'd like to see how the zero camber feels.
Thanks for the help, i think this would be the way to go now:
Caster: Around +3.5 (Drivers 3.25 - Pass 3.5 to allow for crown in road)
I have my camber at -.5 and caster +5, equal on both sides since I often drive on 4 lane divided highways were the the left lane slopes the the left and the right lane to the right. With +5 caster the effect on the crown on most any road is hardly noticeable, right or left.
I have a 55 4 door wagon. New custom frame, upper (fully adjustable ) tubular control arms, Tubular lower control arms, 1 inch front sway bar, rack and pinion steering, 4 wheel Alden coil overs, rear 4 link with panhard bar. I am getting aligned tomorrow. What should I tell the man I want? This is a once in a while driver, once in a while canyon car. Advice please. Thanks