I have a 67 with a 351w out of a 74 Galaxie. I have the standard 67 A/C sb Radiator (for 90 deg water pump) and a V belt system. I keep blowing out the Water Pump Gasket on the bottom of the water pump by the crank. It is the inside gasket between the backing blate and the actual water pump. I have replaced the gasket about 4 times and it keeps happening. I have replaced my thermostat twice as well. I have a non collapsible lower rad hose. I have a 13lb cap and Im pretty sure I have a correct flow direction pump. It appears that I have been creating too much pressure in the water pump housing. I dont understand what it is doing. I warm up the car before I drive too. I even took it to the strip and had no problems doing a dozen passes at 6k RPM but a day later I blew the water pump gasket out when I took it to 4k RPM. I am lost. Thanks in Advance.