The Perth Motorplex is a racing venue about 30km south of the Perth CBD, just off the Kwinana freeway. And its a great place to go, not only on weekends, but also during week nights. I have been there for numerous events among them where car sound competitions, drag racing, burnouts, monster trucks and the sprint cars racing at the speedway. Make sure to check out their website for times and prices.
I’ve watched the sprint cars as well.
They had a demolition derby at the end where they smashed up a whole bunch of cars!