the valve does that automatically...
Once the DRCV valve opens- both upper and lower chambers are at equal pressure, so anything after 50% travel the chambers are equal. When the shock is extending and the valve shuts at 49.99% travel, the chambers are still roughly at the same pressure, but now separated since the valve is shut. The upper stays stuck at this pressure since the valve is shut, but the lower chamber continues to decrease in pressure as the shock extends. In compression- the pressure in the lower chamber builds until it matches the upper chamber pressure right at 50% travel, right when the valve opens.
You shouldn't feel the valve open on a properly functioning DRCV shock...
Once the DRCV valve opens- both upper and lower chambers are at equal pressure, so anything after 50% travel the chambers are equal. When the shock is extending and the valve shuts at 49.99% travel, the chambers are still roughly at the same pressure, but now separated since the valve is shut. The upper stays stuck at this pressure since the valve is shut, but the lower chamber continues to decrease in pressure as the shock extends. In compression- the pressure in the lower chamber builds until it matches the upper chamber pressure right at 50% travel, right when the valve opens.
You shouldn't feel the valve open on a properly functioning DRCV shock...