I down shifted earlier at about 85 mph from 5th to 4th as I entered a decreasing radius off ramp....(sweet!!) As I got into the curve I down shifted to 3rd at about 65 mph (again ..sweet!).........

My question is....what's the max speed you have successfully downshifted ( to 4th from 5th)....out on the interstate...when meeting a challenge....& your intention is max acceleration...

I know mags say max speeds in gears are 31, 53, 80, 111 , 138 & 151......but practically speaking.....does it make any sense to do down shift much past 85....(5-4)?