does anyone know the best way to test handling?

as in cutting out driver error as much as possible from test to test?

changing out the sub-frame i think it is, to a traction bar, and the company is saying it will improve handling, is there any objective way of testing this with somewhat hard data?

 

The way I would test any suspension change is with a skid pad and a device to measure body lean, and another to measure cornering G's. Higher cornering G's are more important than body lean. I know how
to take out the body lean. My '89 Accord can demonstrate......

What they sell as traction bars should really have another name,
but they WILL improve the way the car handles. Some designs are better than others.

A bit of advice: measure carefully before installing them, and get the alignment checked afterward. Some people are tempted to crank them
tight, and it puts the alignment off.-Bob