The DDC-1T Pro can be over-volt modded by adding the jumper-bridge to the PCB.
Before purchasing, verify that indeed the pump is a DDC-1T Pro or an Ultra. Those are the only two that can do the PCB mod.
Now an quick FYI. Modding the Pro or Ultra will reduce the pump run life if the up stream restrictions are great in the loop. Also, the black impeller with the volt mod will be nosier vs. not doing the volt mod and using a performance top with the black impeller.
I only have the DDC-1T pumps.
Take the info from a pump maverick.
.Edited by bmaverick - 10/4/11 at 8:34pm