Today I bought a Used t3 turbo. On the oil feed port, a brass fitting with lock tight is on it. On the other end of the brass fitting it has threads for a fitting. I've been looking around for turbo oil feed lines and they come in 3 AN size stainless steel braided line and 4 AN size. I need to know which one threads on? Is their anyone with 3 AN/4 AN size fittings around here... or can I go somewhere to like Discount and see which one screws on? I just want to know what threads on so I can buy the correct line. I have a few brass fittings here in unmarked bags and they screwed right on it. Whats the difference between a 3 AN and a 4 AN? Really need some help, would like to buy the correct line being that their not cheap and I don't want to go through the hassle of buying another one.