Old converter stalled at 3000 rpm(stock 11" converter tweaked to get 3000)........new converter,9" stalls at 4200 rpm and it does! However! at 2200 it takes more throttle then the 3000 rpm converter did(the rpm that i leave the line at). ten feet out of the hole it's a 4200 rpm. its at the initial hit that it stumbles. And when i say stumble is anything from a micro stumble to a full on stumble that i have to take my foot of the floor to keep it from dying.