I'm trying to delete as many hoses as possible for the 20r. Can I plug the black circle? If I plug the black circle, can i connect the blue circle to the heater core? Also, what's the red circle?
Black circle--yes block it off if youre not going to use the stock carb(water choke) Blue circle-- yes but you have to make sure you have a in and out going through the heater core. If i remember right, this line is a return. Red circle--i believe is the coolant temp sensor
Plug the black and blue. The blue is the return line to the water pump from the carb water choke. The heater core is serviced by a separate line coming out under #2 & #3 cylinder on the intake manifold. The red is your temperature sender. Leave that alone.