Well I have routed the bypass and put in the Mr. Gaskety thermostat and it cools the engine much more consistently with the bypass than it ever did even with the old pump. The engine just climbs to 185 and and stays there. So the problem was cavitation because there was not sufficient return flow to the pump to provide circulation which the bypass solved. Probally could have benifited to old pump too
Thanks oldbogie and everyone else. worked out great!