revving up

“Design engineers were thinking about revving up the tractor’s horsepower or reconfiguring the controls for operating the tractor.”

Simon & Schuster: Diffusion of Innovations

“He drove slowly and cautiously to his bungalow in Clusterwell, to be followed half an hour later by Katje Doorn, revving up the Mini and making it roar and squeal its way through the villages to Kingsmarkham.”

A Guilty Thing Surprised

“Reinitiated conduits whined, gradually revving up until the familiar hum throbbed steadily.”

Simon & Schuster: Breakdowns