The man wants MORE caster. How about this idea?

Bodyperson said
I "think" I am agreeing with you but measuring from a "rack" I'm thinking you are talking about computerized equipment. That is how computerized equipment do it. Not to mention set-back. How could we ever take that into consideration. I guess there is some trigonometry involved there. Without taking set-back into consideration, we end up setting toe equal to set-back.

I'm talking about measuring toe directly, because that's how I do it. And it's actually how toe is defined.

A modern alignment rack does the toe measurement from the spindle/hub, because it does all of its measuring from the hub. But you hit it, that's a computerized system and it's programmed with the equations to come up with those numbers.

Dale Davies said
When measuring and setting toe, the measurement is taken horizontal or parallel to the ground, at a height about the center of the spindle or wheel bearing. Caster and camber are already adjusted when you check and adjust toe. The 6°, do not sweat it as it makes no difference to toe. If this concept is too difficult to grasp, take it to an alignment shop.

Dale Davies said
My good gosh, your ship sailed about half an hour before you got there. To measure toe the old way, you jack up each front wheel and rotate the tire as you put a chalk mark around the circumference for each wheel about the center of the tread. This gives a true straight center to measure from. When you let the wheels down again you roll the car back and forth a few inches to settle the suspension. The final roll should be forward as you drive. Then toe is measured between the two marks and compared between the from of the tires and the rear, at the center of the hub height.
Modern alignment equipement does this by laser and computer.
The contact patch has nothing to do with toe other than being a source of excess wear if the toe is wrong.
Camber has a slightly different settling spec left to right to compensate for road crown. Caster can be used that way also. This is taken into account in the factory setting specs.

I'm well aware of how to measure toe "the old way", that's how I do it. The better tool doesn't use chalk either, it scribes a line on the tire tread.

Toe is defined as the difference of those measurements between the tires. How the modern alignment equipment does it is a computer short cut, it's easy to program the computer to measure the toe from the hub/spindle, and doing it that way you don't need a tech to set up a different measurement or more equipment. You just do it all from the single attachment point. It's not necessarily the better way to do it, it's just the faster/easier way if you have a computer doing the math and an unskilled tech setting up the equipment.

The contact patch is the only thing that matters. Maximizing the area of the contact patch under all of your different driving conditions is what should be determining what your alignment settings are, maximizing traction and even tire wear. Otherwise you're just looking at a bunch of numbers that don't mean anything.