I'm rebuilding a '92 LS motor for turbo. Have forged internals, etc.

Won't be boosting until I break it in. Motor is going to the machine shop this week and I'd like to have them tap the oil pan now so I don't have to mess with it later.

What do I ask for? Size, etc.....also where exactly on the oil pan would be the ideal place?

 

you are talking about the return line right? i dont know much about the size but you want the fitting to be around 1/4 up from the bottom of the pan. and from what i hear the it is best if the line makes a 90 degree angle from bottom of turbo housing to the oil pan. anyone correct me if im wrong

 

Fitting size should be 1/2" NPT (National Pipe Thread). A 3/8" fitting would be as big inside as the -10 AN line you should use, but bigger is always better. 1/2" is the defacto standard, and most common to find the right brass fitting at a hardware store.


btw - search for breakin techniques, all you really need are the rings to seat properly, and that can be done in a day if done right (a week at most). Not trying to start a discussion on it here, just read it (its a big thread) and decide for yourself.

 

OK so regardless if I go with 1/2" or 3/8", I can still adapt lines to fit that as well as my turbo (wanting a T3)??
sorry i'm a turbo n00b.....
Should this be tapped so the hole faces the radiator or the firewall.....or other??

 

you need to tap it high on the pan and close to where ever your turbo's return will be. every set up is different depending on turbo/mani, so the best bet is to mock up the mani/turbo and figure it out from there.

don't mess with brass fittings, get a weldable -10 AN male connector and have it welded to the pan.

 

for an ls your return line is the short stubby line. the fitting should go in the front of the pan 1/4 way up from the bottom. the feed line is the long skinny one. it goes on the back of the pan facing the firewall.