Need to pick the brains of the knowledgeable on engine thermostats for 3.8 liter engines. I believe the common garden variety ones do not work correctly in our engines (although they fit the housing) as they have no provision to close off the bypass passage when they open. The the usual suspects have different types. The one from Moss is not what I want as it is a 180F version. SNJ Barrett show one at 74C with a plate at the bottom which I assume functions as a bypass shut off. Yes, or no? And Welsh Jaguar shows a different design one that in the photo is cylindrical at the base. Also 74C. Does this one also shut off the bypass? Which works better if there is any difference? There is a considerable difference in price as well.
