Hi turk !
The voltage in the outputs depends on the physical electronics, not in the code, so it can't be modified changing the code.
The only way to change the gate output voltage is modifying the electronics. If you are into DIY/electronics I can give you some advice on how to do so. But you need to open the Eloquencer identify and change at least 8 resistors (10 if you want to change reset output and clock output). I strongly recommend to have some previous DIY/electronics experience if you want to do so, the components are SMD.