move/get into top gear
From Longman Dictionary of Contemporary Englishmove/get into top gearmove/get into top gearBUSY/HAVE A LOT TO DOto begin to work with as much effort as possible The party’s election campaign is now moving into top gear. → top gearExamples from the Corpusmove/get into top gear• Accelerate smartly so that you can get into top gear as quickly as possible.• It was ready to move into top gear at very short notice.