A lot. The EB generates a lot more retarding force than just throttle off. How much is dependent on rpms. Could be anywhere from 5x to 10x more retard. Without the TC locked all it is doing is spinning thru the fluid and heating it, throttle closed the TC does not lock.
Most of what you are getting now is parasitic drag from the gear reduction by down shifting to second with no EB, add in the EB and it is generating retard force plus the parasitic drag. Without TC lock it just hits the fluid coupling harder. With TC lock and no TV pressure ramp, it will start slipping clutches and the front band.
Most of what you are getting now is parasitic drag from the gear reduction by down shifting to second with no EB, add in the EB and it is generating retard force plus the parasitic drag. Without TC lock it just hits the fluid coupling harder. With TC lock and no TV pressure ramp, it will start slipping clutches and the front band.