Hold the brake as tight as you can to prevent the wheels from spining. Put the throttle to the floor and see where the tach stops. That would be your brake stall. Any stock performance motor should have at least a 3000 stall converter. Different motor combos stock or not will stall different. The highest I saw a factory 340 converter stall with my own eyes was 3100. the lowest was 2700. Normal is around 2800. I have a 80's 318 4bbl police 904 in a duster right now and it stalls at 2500 but it spins the tire. Once the car gets a suregrip it will probably go a little higher.