Ah I was at work so not possible. Different classes of cars in one race expose people to other fast cars and also make racing interesting as drivers use back markers to their advantage or sometimes disadvantage.
Also Australian racing in previous decades has shown how smaller engines can be just as competitive. You can't discount the relevance of XU1 toranas, E49 chargers, mini minors, S4 EH's etc. They were all just as good to watch as a phase 3 falcon.