What is the "ideal" way to do the oil drain line?
 

I have seen how it is done with a drill and tap. It seems to me that is a compromise given that the pan is so hard to remove that nobody wants to do it just to add the oil drain. But my engine is on a stand and the pan is already off.

Welding a bung might be nice but I can't weld aluminum.

Why is the usual location so far forward? Is there interference from something otherwise? Obviously where a straight shot down from the turbo ends up will vary depending on the manifold design, but with my non-exotic cast manifold, a straight down oil return will end up right around the rearmost part of the shallow end of the oil pan. The FM instructions (for example) show the drain all the way at the front of the pan. What am I missing here?

This bulkhead fitting seems like a good alternative to a tapped hole and the usual brass fitting.

This is why it's so far forward:

Attachment 206815

Here's what I used:

Attachment 206816

there is a baffle plate running along the side of the pan wich you will hit if you drill further back even drilling at the front you have to watch the oil pickup pipe if you drill in too far if your engines out take your sump to an engineer they will gladly weld a alloy fitting on for you

here is why

I would just take it to someone who welds aluminum. I can't see a shop charging more then $30 to weld a bung onto it.

Drill and tap it like FM shows, up in the front. Then thread it in with some JB weld around it.

nice pictures..really helps me out.

Hmm. Thanks for the pics. The pickup tube might make it very difficult to put a drain directly below the turbo. (Though I suppose a bung could be welded such that there was no internal clearance needed.)

What about mounting the drain in the deep part of the pan, on the side of the sump? Seems like it would result in a shorter drain line with less angle.

I SURE CAN!! Do you know the prices to weld aluminum? You will be surprised, the gas and wire required to weld it is quite pricey

You're overthinking it man. Just put it up front like everyone else, you're not going to get any more flow by ensuring it's exactly straight up and down.

Here's mine (seems I've been posting this pic a lot lately!), it's not dead-on 180* but it does not want for flow!
Attachment 206811

Edit - Besides, think about it, your feed line is likely 1/3rd the size of the drain, and is probably restricted in some way.

I had the oil pan off so I had a bung welded. It cost $40 plus the bung from summit which I think was like $5. It's not necessary at all to have a bung welded, but I just felt like over doing it.

The failure mode that part would be the nut coming off in the pan, and having to drop the pan to get that loose metal out of your engine. I would only use a bulkhead fitting with an externally-tightened nut.

Since the pan is off, a welded fitting is your best option. If the aluminum isn't cleaned really, really well, there's a high risk of porosity that could cause an oil run. So clean it really, really well and take it to a good shop.

Assuming it doesn't have a negative impact on packaging or access to turbo fasteners, etc., the shortest run possible is generally a good way to go. Moving it slightly forward of the turbo so the hose doesn't block tool access to the drain fittings and stuff might be a good idea.

Re: overthinking it, yes, probably. But I would prefer the neatest solution and I have the time to do it right. I need to make sure the engine mount won't be in the way though, your pic makes that clear.

Re: failure modes with the nut inside - I would safety wire it if I did it. Right now I am leaning towards having a bung welded. I need to find a good welder anyway, since my cast manifold has a crack in it. But I'm sure it will cost me more than $30. Skilled labor is not cheap in these parts...

Since you are having the manifold crack welded anyhow, I would go ahead and have the bung welded to the oil pan - my guess is it's gonna be pennies to dollars.

I had it done. Cost me $40 because he had to clean the oil pan out first. I wasn't surprised.

You want legit? This is it:

Attachment 206743

That's the ticket. Perfect. Would you choose the 45 degree AN hose end again? Is that -10 or -12?

i assume so his oil line is more linear.

kday, has your car AC or PS? Maybe in the 90 NA is easier to route, but take a look at the 2001+ with AC and PS

Attachment 206656

haha, yes, that is pretty crowded. I have a 96 engine that is going into the 90 and I'll most likely remove AC and PS.

Kday, buy a 60 degree fitting. I did the 45 but most people have interference issues with the steering rack. Mine BARELY clears. It's a -10AN fitting. I also used nylon braided line so I don't cut myself every time I look at it. If you're using a BEGi manifold, you should only need a foot (I took 2ft of -10AN and ended up using 8") since you aren't going down to the front of the motor.

Cool, I'll get the 60 degree fitting. I have a bunch of -10 stainless braid hose left over from another project. I'll try not to look at it too much...