Or maybe be good AND have open speed limits like the NT did until 2003.
I once did 400 Km of dirt and 100 single lane two way, sealed from Kintore a remote Aboriginal community on the WA border, to the Stuart H'way turn off about 25 km North of Alice Springs, then turned North and did 1500 km 2 lane wide tar straight through to Darwin. 2000km in 17 hours with fuel stops about every 500Km. Two extra range tanks and an unlimited fuel card!
Flat to the pedal on my diesel HJ75 Troopie or Nissan Turbo Patrol I could average 140kmh on the dirt and and 155Kmh on the sealed highway maxing about 160 and 170 on each surface.