Dynamic converters?

I'm not sure what you have for a combo or convertor... List the full details. Also, to check for stall speed you need to be in 3rd gear and cruising at light throttle, then floor it and see what it stalls at. Then you can apply the brakes and do the same and see what that stalls to. First is flash stall, 2nd is brake stall. They will be different. Most any perforamance convertor will slip some at low rpm like that. So what did they sell you?