Oil Filter Adapter
With the headers, the adapter is absolutely necessary. I'm wondering if other people have experienced less leaks with iron than aluminum. The oil leak is terrible when the car is cold, but goes away when the car warms up. Since aluminum expands more than iron and steel, perhaps the aluminum adapter is growing more than the steel bolt and the oil leak gets sealed up when the engine is hot. Would an iron adapter grow less than the aluminum one and crush the adapter gasket less?