up·shift 
/ˈʌpˌʃɪft/ verb
up·shifts; up·shift·ed; up·shift·ing /ˈʌpˌʃɪft/ verb [no obj] : to put the engine of a vehicle into a higher gear
▪ She upshifted into fifth gear. — opposite downshift
▪ She upshifted into fifth gear. — opposite downshift
— upshift noun, plural upshifts [count]
▪ an upshift into fifth gear
▪ an upshift into fifth gear
