Turbo Oil Feed Line Elbow Fitting


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Need help in verifying & identifying the thread size of the 90 Degrees Brass Elbow for the oil feed line that sits atop the Turbo. I believe its a 1/4 in Pipe Size, Inverted Flare x MNPT. I'm thinking this is it, but not sure. Any help would be appreciated.

I think it's 1/8" NPT threads to 1/4" hard flared pipe.

Measure the hole in the turbo to be sure. 1/8" npt hole size is bigger than 1/4" see below.

"If you have a 1/8'' NPT pipe tap, the R type is the appropriate drill bit to use with this tap. If the pipe tap is tapered, the ideal drill size is 21/64mm in fraction form or 0.339''. For non-tapered or straight pipe tap, use a drill size of 11/32mm or 0.344''.
I'm looking to install a AEM Oil Pressure Sensor (1/8" NPT) to the oil feed line that sits atop the Turbo using a couple brass fittings:

1. Inverted Flare Fitting, Brake Line Adapter, Male Connector, 1/4" Tube OD x 1/8" NPT Male &

2. Brass Street Tee 1/8" NPT Female x 1/8" NPT Male x 1/8" NPT Female, Male Run Tee 3-Way Pipe Fitting

3. And maybe needed 45 Degree Street Elbow 1/8" NPT Male x 1/8" NPT Female Brass

Is there any con's to placing the Pressure Sensor here rather than down at the other end of the oil feed line by the Oil Pressure Switch ???
Is there too much vibration atop the turbo?

All opinions much appreciated.
On my cars I remove the switch @ the feed block, convert the switch port to -4AN, run it up to a homemade j block near the AC box, and put the switch and a pressure sensor there.
That gets the wires up out of the oil leaks, and heat.
Is there enough slack in the pressure switch wire to reroute it to / near the AC box ? How did you fabricated the j block ? Do you have a pic of the j block ?
Don't have a pic of it.
I used a block of alum about 1 x1 x 3-4". Drilled and tapped for pipe threads.
A -4 AN adapter to 1/8" NPT for the line and I think 1/4" NPT for the sw, and 1/8NPT for the gauge sender.
The wire was cut back in the harness and extended. The original sw boots were oil rotted, so the plug went away.
Both my cars have the pressure line up top at the modified stock fitting it's easy to do it that way.
The only time you will have an issue with readings is if you have a restrictor in the line at the turbo for a DBB type that uses or needs one.
That will make the reading a lot higher especially with cold thick oil, when hot it's pretty accurate however.
If you don't have that type of restrictor in the line it's an easy place to work.
Here's a pic. of the mechanical gauge hard line installed in 1/8" NPT fittings.