Minimum impedance seems is the lowest impedance value in the bottom right graph. This shows the load (per frequency) presented to your amplifier. in your case, your current design looks to drop to 2.5 ohms around 350Hz. Although you are using 8 ohm drivers, when we parallel them, then apply further parallel "legs" in your crossover, we lower system (overall) impedance.
I personally design all my passive speakers to have a 3 ohm minimum impedance (unless you have 2 Ohm stable amplifiers... maybe you do).
The black line (reference angle) is what you are going to hear. When we see the black line dip below the individual driver curves, that immediately tells us the drivers are canceling eachother in some way. This is largely undesirable. We want the drivers to sum, such that the black line is always the same (or higher) than the individual driver curves.
You mentioned you are planning to measure the drivers in cabinet. If that is the case, I'd discard this crossover completely as the source data you are using now will be quite different to what you measure.
Treat this attempt as a VCad learning exercise, but nothing more.
I personally design all my passive speakers to have a 3 ohm minimum impedance (unless you have 2 Ohm stable amplifiers... maybe you do).
The black line (reference angle) is what you are going to hear. When we see the black line dip below the individual driver curves, that immediately tells us the drivers are canceling eachother in some way. This is largely undesirable. We want the drivers to sum, such that the black line is always the same (or higher) than the individual driver curves.
You mentioned you are planning to measure the drivers in cabinet. If that is the case, I'd discard this crossover completely as the source data you are using now will be quite different to what you measure.
Treat this attempt as a VCad learning exercise, but nothing more.