Police detected four vehicles travelling at more than 130km/h within hours of each other near Ballarat yesterday.
A 19 year old was detected at 147km/h on the Western Freeway at Invermay last night, with the same Highway Patrol officer detecting three more drivers within the 130km/h to 140km/h range during the evening as well.
The Ballarat teenager was caught driving at the high speed at 6pm in an unregistered vehicle.
He was also unlicensed and had his vehicle impounded for 30 days under the State Government's hoon laws.
Within hours of that offence, three other drivers were all detected in the same spot on the Western Freeway travelling between 130km/h and 140km/h.
That section of the Freeway is posted as 100km/h.
The three drivers all had their licenses suspended on the spot.
The speeding offences come as police launch their back-to-school road safety campaign today.
Police will enforce 40km/h zones around schools and also focus on drivers performing illegal t-turns, dangerous parking and other traffic-related offences around schools.