Oil Temp Sensor Location
 

Other than tapping another hole in my pan right after tapping, flushing and refilling with new oil for the turbo drain, where are all of you locating your oil temp sensor?

If the pan is the only option where did you tap it? Sensor is a 3/8 npt that came with the Maxigauges.

There are oil filter sandwich plates that have a tapped boss OR you could add a tapped boss to an existing sandwich plate IF you're using one (for an oil cooler.)

I will be tapping my pan for a GM coolant temp sensor to use for oil temp. Make sure that you tap the pan on the passengers side. It is a pita to deal with a temp sensor wire around your hot manifold.

what about the oil feed ports on the back of head??

There was some discussion about using these as an oil feed port for a turbo but don't see why they couldn't be used for oil temp.

If you guys have the pan off the engine, the way to do it is a weld bung

https://www.miataturbo.net/attachmen...ine=1396288064

The pan is so thin that I just wasn't comfortable with like 1 thread worth of engagement. I added 1/2" NPT for oil return on the drivers side and 1/8" NPT for temp on the passenger side below the baffle. I was worried with the sensor interfering with the subframe but I guess I'll figure it out shortly.

https://www.miataturbo.net/attachmen...1&d=1396302913

https://www.miataturbo.net/attachmen...1&d=1396302913

Top of the sensor is 1.5" below the baffle. I do wish this sensor was a bit shorter though.

Reminds me, I need to look, my car came with a remote oil filter. Need to see what was there for a mounting plate in lieu of the sandwich plate.

Wow that bung would have made life easier, I used an aluminum half coupler when I welded mine on. To the drivers side rear of the pan... because thats what Hustler said in this one post one time and it seemed legit.

Yeah, I just don't know if it clears the subframe yet :noes:

Got a pic of your install location? You mean yours is like, below the bellhousing?

Mine's like the mirror image of yours on the drivers side, but in the same set of ribs as the oil plug. It may have hit the subframe a little bit while dropping the engine in.

If it hits I have a spare weld bung, but its not something I look forward correcting.

https://www.miataturbo.net/attachmen...ine=1396308575

Not my pic, but its gonna be damn close at any rate.

Also, don't even think I welded that myself. Mad props to Gesso for being a TIG ninja :bigtu:

I run mine just above the oil drain plug, it is nice and out of the way.
Let me try this link
https://www.miataturbo.net/attachmen...ine=1396314712

I can't see your image, but I'm starting to think that's what I should have done. Problem is, I don't know how much oil is actually sitting in the pan at 7,000rpm and I wanted to get it as low as possible.

Image working for anyone else?

Did not want to jack the car up so it is a bad phot, but you can see that it is above the edge of the powerplant frame.
https://www.miataturbo.net/attachmen...ine=1396315083

Did this location work out for you? Is it low enough in the pan?

That position is below the low level mark and it is pretty stable on the track so I believe that it is an accurate reading, not sure how much oil is in the pan at 7k but I hope that it would have a couple inches worth or I would be seeing oil pressure drop on the straights.
That location has the hottest oil in the engine and that is what I want to keep an eye on.

Is there any data on deltaT between the sump and either a sandwich plate or an oil cooler/remote filter? I doubt very much whether there would be any appreciable difference in T between the sump and sandwich plate, although considering that the oil pump almost certainly adds heat to the oil it might be hotter than the sump :confused:. I have always used a location downstream of the pump, but I am not convinced that a few degrees one way or the other is enough to get excited about - unless you are right on the upper temperature limit for your oil, in which case sensor location is not something to dwell on, and more cooling is your focus.

I am about to install temperature and pressure sensors on the inlet side of my cooler in a engine>cooler>filter>engine setup. Next time the engine is out I might look at an alternative (or additional?) sensor location in the sump or on the sandwich plate.

I agree that the pump will increase the oil temp when pressurizing, my sandwich plate is a Moro with a 170f thermostat and did not have a temp sensor port so I wanted to stay away from measuring oil temp before the oil cooler because the cooler does not see oil flow until the thermostat opens.
I do try not to romp on it until I see the oil temp coming up and is over 100f (that can take a while in cool weather) so the oil temp in the sump or sandwich plate is not a bad thing IMO

https://cimg8.ibsrv.net/gimg/www.mia...72e31dfe55.jpg
another option is to drill and tap the oil drain bolt. Volvo did this using VDO sensors years ago. I'm using this, but I feel this location is cooler than what the rest of the motor is seeing.

I'd be wary of putting a sensor in that location, where it's so exposed. One stray rock or chunk of ice would easily snap any temperature sensor I can recall seeing.

I agree, it's an easy solution for testing. Welded bung would be better while you have the oil pan off.