thank you. By reading those attachments I have come to the understanding that the radiator is, indeed, the path of least resistance.

Why else would their R&D staff decide to use a t-stat to LIMIT flow through that region?

If the block and head were less resistant to flow, how would coolant ever circulate through the radiator to cool them under normal circumstances? It is only when there is too much heat, that the flow through the block and head is limited by the bypass valve so that MORE cooling will occur by sending coolant through the radiator in greater proportion.

ie.. IF you begin to overheat the engine w/o your t-stat, you have no chance of cooling it off b/c there is no mechanical means of directing flow based on engine needs. But until then, you are over-cooling the engine due to the nature of the system.

It appears that the t-stat is the dam, and once OT is reached, God opens up the flood gates to nourish the weak under-cooled. But the lord taketh as well, he reduces the flow through the block by proportioning the flood to the areas that need it more.

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