with afr heads an air gap and a old style block do i have to run a bypass hose from the intake to the water pump or can i just block them off? I have blocked them off but temp seems to be up about 20 degrees,,,
Many after market performance water pumps don't have the by-pass port or have it plugged. So, to be safe, drill a couple of .125 holes in the flange of your thermostat. This will help the water circulation in the crucial areas of your heads while the thermostat is closed.