Still waiting on the headers to arrive before moving on ... I want to do as much as possible with the engine out of the car, knowing where I have room to work and where not. Once she is in the car, I will fine tune my measurement. So, I currently working on the oiling lines. I have drilled the block and threaded in a 45 degree 1/2 NPT/-10AN fitting. The return line from the turbo will be -10AN ... pictures of the drain side of the turbo will follow. Here are pictures of the block location that was tapped and a reference shot showing the location with the stock headers to show clearance

3/4" hole drilled to accomodate 1/2 NPT (ID) fitting


-10AN return line installed


Reference picture of tapped location


In case you want to debate the tapping of the block vs. the pan, don't bother ... it's been done in this thread where I also posted these pictures on the subject matter of oil drain material used.

Now on to a questions:

1) What is the thread size of the oil supply galley in the head nearest the firewall (next to the DPFE sensor)? I search and only came up with a single thread and IIRC stated 1/4" NPT, but that seems rather large to me since most turbo supply companies cary mostly 1/8" NPT.

2) Also, what size reducer (oriface size) should I use to reduce oil pressure to the turbo?

Last edited by fastcougar; 02/28/06 05:27 PM.
For Sale: 1997 Explorer XLT V8 AWD