Update: A while back the guy who does all my work had a buddy with a fountain that was having a overheating issue. He had a crossover with bypass and thermostat, and even though his water and oil temp was getting hot, the exhaust was nice a cool. Well they figured out that with the bypass hose being very large on these kits, it would just flow most of the water straight through the bypass and out of the exhaust. So he put a washer in the bypass hose right against the tstat housing to restrict the flow and it fixed the over heating. So we did the same on mine, and water pressure jumped right up, too much actually. We are playing with different sizes to get the pressure right. Basically the bypass on these kits flow too much water, and doesn't provide much resistance to push water through the block with much pressure, so the water just takes the path of least resistance and flows straight through the bypass and out of the exhaust once you have any kind of pressure in the block. Is this not a common issue with people running the crossover with bypass and tstat?