If it can not stay in the Radiator long enough It will not cool!!!! Another words If it flows to fast It doesn't get a chance to cool Period.It will cool to a small dergree But Not like it should.Not much different then if your not Getting enough air across the fins of the Radiator To pull the Heat off of it. If it flows to slowly Or not enough air flow over the fins the motor can Over Heat Or run hotter then it should. Greg what Thermosat are you running now?
God doesn't like ugly.
