When the car is dyno'd and you have a 3400 stall and the dyno operator starts after the rated stall speed would the tq readout be lower then if it was started at a lower rpm?

I heard that tq multiplication is less after the rated stall speed of a converter...is that correct?

I'm just trying to come up with answers as to why i lost peak torque after my cam install.

 

Torque multiplication decreases as rpm increase. It is a downward sloping curve. The converter will increase tq past the stall speed to about the point where it couples up (not the same as lock-up). You can use your shift extension as an estimate. Above that you will lose 3 - 6% compared to a locked converter.