a lot of people dont use them. be sure the stub at the metering head is blanked off though. im sure it will be if someone has removed it. the amal ha 3 ports/ actuator/housing and vent to atmospere(stub at metering head). the amal will cut boost if the ecu detects a problem. without it theres no safety cutoff. with appropiate gauges and a feel for whats going on the amal isnt needed imo