If you stated it, I apologize... But by any chance do you have an
oil thermostat? I installed a Canton thermostat on my Cobra before I even drove it for the first time. I homemade an aluminum bracket for it and mounted it to the forward cross-member and plumbed it in with the usual AN braided line. I think ERA has a "rough drawing" of the plumbing schematic in their "additional tech" portion of the website. And in regards to the
oil viscosity, which I know I'm gonna start a holy war here but... it depends on the clearances of your rod and main bearings and environment your driving your car. I personally built my engine for my car and can tell you that I run straight 40W but that can be another thread.