Vic drug driver detected after speeding

A Victorian driver has been caught allegedly speeding while on drugs with a car full of passengers.

The 20-year-old tested positive in a roadside drug test after police detected him travelling at 169km/h in a 100km/h zone on the Geelong Ring Road about 7.30am on Monday.

He had four passengers in the car.

The sample will be sent for further testing.

The man is expected to be charged with drug driving offences.