Just north of the city is Calder Park, with its motor racing complex for drag racing, circuit racing and with a speed bowl (NASCAR style) tracks. Off-street drag racing happens weekly for those with street cars. The other tracks at the complex are used by a variety of types of motor racing. You can arrange a ride in a racing car around these circuits or even drive a V8 race car yourself (as I have) around the track circuit. Recommended for petrolheads.
Calder Freeway (Sunbury Melways map ref: Map 3 A4);
tel: 61 3 9217 8800;
www.motorsport.com.au
Updates
This whole motorsport experience is now more exciting... as Australian Motorsport licence holders (like me) can take their own race cars (like my V8 touring car) out to Calder Park and have a day's testing/racing/practice at one of the monthly Calder Park 'Open Practice' days - awesome!
Is this your business?