Caltrac operation on leaf springs

I can partially answer this. I myself never operating a car with them. I do have a set ready to bolt on a Duster.

The rear shackle question I am not totally sure of. I can still, in my head see the rear shackle moving.

The spring has two functions. Stop axle wrap and hold the cars back half up. The ride quality may be diminished. But you still need the springs to hold the rear of the car up. Since that is the fact of the matter, the springs must still have an impact on ride quality.

For a drag race, street or strip, once you figure out where the bars are to be set, there should be no need to readjust them over and over unless your at the track looking for every mast millionths of a second to win. Changing race conditions would have you looking at everything anyway.

However, for a street strip car that isn't competing for the higher level bracket racing Wally, everything would be fine.

I would note that changing to different tires would probably have you tweaking the bars for best reaction and times at the track and perhaps the street if there is competing driving. Just by way of how one brand/compound tire works vs. the last tire used.

All knowledge gleaned from constant reading from the guys that have Cal Track bars in there cars competing or not.

I got my bars as part of a parts deal. There split mono springs are next.