MyE28.com

My turbo has a 3/4" return hole and a ~5/16" feed line. I was thinking 12AN and 4AN lines. Sound right?
And what size taps will I use on the pan and housing?

I used -4 on my supply line and tapped the oil filter housing. On the turbo I used a -4AN billet adapter from Function7. I used ShawnD's website as reference for drilling the oil filter housing. As for my turbo drain, I used an adapter which was threaded for 1/2" NPT. I also tapped my oil pan 1/2" NPT (it needs a 45/64" drill) and used some quaility SS Swagelok fittings for the line. -12AN is very large but would work well and -10 would probably work. Mine is only 1/2" SS tubing and I have no issues with oil drainback. What size hole to drill will be determined by what fittings you choose to go with.

Thanks. It looks like I'll probably use 1/2npt for the drain.