What size AN fittings / hose to use for GReddy oil return?
 

I have an oil pan that a friend is going to drill a hole and weld a AN fitting to. I want to order the AN bungs from Jegs to weld to both the pan and to the turbo return line fitting.

Is -10AN the correct size?

Is there anything else I should have the pan drilled and fittings welded on for? Oil temp or something?

We use -12. The hose fits very tightly on the Greddy oil return tubing. We heat the hose with a heat gun to make it easy to work with and lube the Greddy tubing to work the hose on.

No real need to weld a bung on the pan. There is enough meat there to just drill and tap it. We use 1/2" NPT.


http://www.lms-efi.com/miata/oil_return.jpg

-10 is fine, -8 is sufficient for smaller turbos. If you can have it welded, do it. While it might not be necessary, you will never ever have to worry about it again. I'm not intimately familiar with the way that the greddy return is setup, but if you can run a fitting into the turbo to a SS line to a bung in the pan like a traditional setup, do it.

While I will agree a -10 is OK for a drain line, a -10 won't fit on the drain fitting that Greddy supplied, which the OP asked about. You need a -12 for that.

So get a new drain fitting...

I was going to have him weld fittings on both ends, oil pan and turbo.

We will have a Greddy Oil Drain Kit posted shortly. It will have a -8 line, and all the fittings and flanges needed. If someone wants to test fit it for me and take photos, I'd be happy to give them a discount.
Thanks,
Stephanie

I got 2 -12AN fittings but when I pulled out the Turbo from the box of stuff I got from the PO I realized the stock GReddy fitting area is to small to weld the -12AN bung to. However the PO had bought an adaptor plate with a theaded hole and a fitting to thead into it on one side and barbed end on the other.

I'm having 1 of the two -12AN fittings welded to the pan and I'll use the aftermarket plate on the turbo. Then I just need to get a fitting that will thead into the plate with a -12 AN fitting on the other end to attach the braded -12 line.

The new stainless line to the turbo that was supplied by the OP is a small diameter compared to what I'm using for the drain. I'm assuming this is OK as the smaller line going to the turbo will keep it at higher pressure while the larger return will help with the unpressurized oil returning to the pan?

If am right in assuming (?) that the standard drain fitting uses a 3/4" OD outlet (-12 AN), why are people even bothering with smaller set-ups?

It seems a bit pointless, given the additional cost of the slightly larger hose/fitting for sump should be negligible. Plus it negates the need to change the fitting on the Turbo.

Or am I getting the wrong end of the stick?

My plan was to tap a 3/4" BSP Tail in the sump, then 3/4" ID hose to the standard fitting on the Turbo.

And more importantly it's big enough that I can use the same drill bit, taps, fittings and hose for the crank breather setup on my '83 Golf (Rabbit), lol.

Dave

You'll have to worry about it the first time you accidentally scratch the sealing face on the fitting and can't replace it because it's welded in place. I'd use an NPT/AN adapter and thread the pan NPT or weld in an NPT bung on the pan if you don't like the wall thickess.

The area on the Greddy turbo where the oil drain piece mounts to is pretty small. The only AN adapter that I could find that would bolt up to it and convert to AN never really fit perfect so I have a tiny oil leak coming from the oil drain as a result. Not enough to cause immense worry - turbo has been on for ~25k and doesn't lose a measurable amount of oil between changes, but it's annoying. I think I went with -10 AN...

Has anyone found a tried and proven way to attach an AN line to the Greddy drain?

I would think a big point of upgrading the oil feed is to get rid of that horrible oil drain fitting on the greddy kit. Put AN fittings on both ends (the pan and the turbo) and enjoy life. -10 is definitely big enough.

this. I did a -10AN weldbung in the first built motor's pan - at some point it got a little stripped and weeped ever so slightly until I blew it up last year.

Guess what I did on the second motor?

vvvvvv

-10 Always worked fine for me on the Greddy kits.

Hmm... after writing my initial comment.. guess what my pan ended up getting... a 1/2 NPT bung welded into the pan. Turns out that's all the local performance shop had on hand, but I'm glad I did it that way now.

Ok, so the drain bung is in -12 AN. Attachment 191360

Now I just need to get the NA fitting that will attach to the plate that replaces the drain on the turbo and figure out how long the braided hose needs to be.

Um, isn't that on the wrong side of the pan?

wait no nevermind. My bad.

At first I was like "ha ha" but then I looked at the location and realized when my friend and I looked at it the night before he took off to weld it we didn't see / take into account the engine mount location! I think this might be F'ed. I'll have to talk to him and see if it it needs to be redone. damn

now that you mention it I think you are fubar'd. I think it has to be closer to the front of the motor.

Well luckily my friend didn't drill the hole in the pan so we can cut the bung off and put in a new fitting farther forward to clear the mount. Live and learn.

This time I'm going to have him put in a female fitting so I can thread in a steel NPT to AN fitting so it can get changed if needed.

I can see why BEGI is working on offering a kit.