[Mahler9th]

I think of bump steer as a characteristic, not a "number you can measure."

Plotting a bump steer curve is a project.

But then once you have a curve, what do you do?

Of course you can use shims to get a different curve.

But what curve is desirable?

The target might be best informed after considering a number of variables.

For a car like mine, I'd seek advice on desirable curve shape(s) from professionals.

My car's builder (also Winders' builder) has informed advice on tried and true shapes.

I imagine that Craig Watkins also has informed advice.

I imagine that Cary Eisenlohr has informed advice.

These people have experience at the highest levels of racing.

There are many products like adjustable tie rod ends, and struts with options to raise the spindles. And rack spacers. Some of these things are designed for simple "sweet spots."

I don't think there is a simple answer to the question "what bump steer curve shape is best."

And I don't think there is a simple single number for "bump steer."