I've looked at both Turbofan's and Mobius' Spa gauge. They work very nicely. I've found that on track, you have a split second to look, and would never notice if they dipped to unacceptable levels anywhere but a straight. For instance, I've wanted for years to monitor my oil pressure during braking. I have yet to remember to do it.

Whatever gauge you get, plan on three giant warning lights for low coolant pressure, and higher coolant/oil temp.

+1 on you wont be looking at gauges while on track/racing.

My plan was to build a BIG YELLOW and BIG RED light, probably shift light type, to mount on top of my "dash". Yellow is better watchout, something's about to go. Red means shut it down NOW!

Yeah warning lights seem like a great feature to have/add. You have only moments to monitor gauges on straights. For temperature, it's not so bad - periodically checking just to make sure the value is within an acceptable range is great, but pressure can fluctuate quickly just based on throttle activity. Warning system is crucial.

Aaand that short moment of time to visually scan each gauge on the straight brings us to the subject of gauge location. Basically the entire center console is out. Perfectly fine for a street car, terrible on the track. It requires wayyyy too much head motion and detachment from view of the track ahead.

My oil/water temp gauges are currently in a pod mounted on top of the center of the dash. The height is good, just below your line of vision looking out the windshield, but I'd like them to be angled towards me instead of pointed at the back window.

In a perfect world with high budgets, most people's answer is to go the opposite way - get an all-in-one dash with all your various senders wired to it, then just set up warning lights for each thing, then go drive and never look at any of those numbers unless lights start flashing at you. But especially with a turbo car, I'm constantly monitoring how everything is behaving, I don't think I'd be happy just ignoring everything and telling myself it must be fine because the warning lights aren't on...

Mounted in a bad location, you won't ever look. In a good location, you'll check them often.

-Ryan

I'm going to act like this is the subreddit explain it like i'm 5.

Let's assume oem 01 motor with all of the oem trimmings (no coolant re-route, oem oil filter stuffz etc, oem radiator) Where would I place senders for Water Temp, Oil Temp and Coolant pressure.

Water Temp - I assume that you drill/tap the spot on the back of the head where a coolant re-route would go?
Oil Temp - Ryan suggested drain plug, some one else suggested at the oil filter. If you don't have an oil cooler or an oil filter relo... do you just add a spacer under the oil filter? If so who sells them?
Coolant pressure - No idea.

Water temp: use the stock location.
Oil Temp: if you are not running oil pressure, then remove the dummy oil pressure sender and put your oil temp there. Otherwise you can tee off that port.
Coolant pressure: harder, you will have to drill for that one. I would use the back of the engine where the temp sensor is.

Welll, you should always have a re-route, really.

So then, for the reroute you add a spacer to the back of the head (between the block and the water neck that your new upper radiator hose will attach to) there are a couple spacers out there, but the one I have from BEGI has several threaded ports in - for the oem coolant temp sender, a barbed fitting for your heater core line (this hole is plugged for me) and also for additional sensors. Can't remember exactly how many ports it has on it, but if you have enough, you can put your additional water temp and pressure senders in there.

For oil temp, the method I use is a brass adapter - has a male side with same threads as a drain plug, with a hole that runs through the center of the thing, and that hole has internal female 1/8 npt threads (universal sender thread size).
Your other option would be a sandwich plate between the block and oil filter that just has ports for senders. This wasn't an option for me because that location is taken by a sandwich plate for the oil cooler. I wish it had a third port on it for a temp sender, but alas.. Anyways, Mocal makes good sandwich plates.

Here's one from Maruha - I'm sure Bill at Miataroadster can get these for you: http://www.maruhamotors.co.jp/miata/parts/oilblock.html
Here's one from Mocal, this is the style for gauge senders, not flow-through for an oil cooler, so I don't run it, so I am not 100% sure I'm linking to the one that fits our cars, you'd need to verify that's the right threads: http://www.racerpartswholesale.com/p..._Plate#reviews
Oh, and absolutely don't get the eBay sandwich adapters that look similar to the Mocal stuff. Just say no.

-Ryan

On oil temp locations:

1. Drain Plug: Pre-cooler location but will see some cooling effect from the pan and stagnation.
2. Oil Filter Sandwich: Pre-cooler location for sensing actively circulated oil.
3. Oil Pressure Port: Post-cooler location for sensing actively circulated oil.

Adjust your expectations of oil temperature accordingly. 3 will be the coolest (assuming your oil cooler works) followed by 1 and then 2 (hottest).

Like Track said, use the stock locations if possible.

https://www.miataturbo.net/attachmen...-along-hed-jpg
Yes I know its a 4W head but the casting is pretty much the same.

Big red arrow is pointing at a metric port that can be drilled and tapped for something larger, like 1/8" NPT. Perfect place for an aftermarket water temp or pressure sender (assuming you aren't fighting with clearance for an EGR tube, reroute tube, etc.)

If you are going to drill and tap the head, you should probably remove the head. If you are going to remove the head, you should think about using the 94-00 head gasket + coolant reroute. If you end up with a reroute, you will have extra ports for more things ;)

The sandwich adapters for oil temp are pretty common. I believe the filter is M20x1.5 (someone please correct me if this is wrong) and you can usually find the sandwiches sold by the same folks that sell the gauges, or turbo oil feeds generally have extra ports in them as well. I know Glowshift makes one but some people have reported quality control issues with that particular brand. Get your search on!

I drilled my oil pan and had a 1/8"NPT bung welded in for oil temp. I wanted a pre-cooler location because the mocal thermo sammich should keep things under control regardless :party:

also, you can use -AN to -AN with 1/8 npt port spacer on a sandwhich plate or on the way out to an oil cooler if you like for oil related stuff.

Because in the back of my head I always knew I was using a cheap water temp gauge, I wanted to keep my stock water temp gauge functional for comparison.

I was about to say that if you get a nice quality gauge that isn't an issue any more, but doesn't the ECU still need to see coolant temp for warmup and other things, in which case you need to keep the oem coolant temp sender, not just yank and toss it to make room for an aftermarket one?

Just keep in mind that anything in-line with the cooler is on the outside of the thermostat in the sandwich plate. Probably not best for temp since it won't read until the thermostat opens.

-Ryan

At least on the VVT heat thats an NPT port.

Well... yes and no. There's water temp gauges that have an output.

Really depends on the setup. On the Miata, i believe the fans are controlled by MS, MS reads the factory sensor, and the gauge has its own deal. (But, the water temp gauge could handle output to ECU as well, moving to a single sensor setup) On my MX6, i have an aftermarket fan thermoswitch, sending unit for gauge, sensor for ECU, and i can't remember if i removed the factory gauge sensor or not.

Escort.... i have an AEM sensor. Feeds Haltech. Haltech controls fans. Haltech transmits temp to be displayed on Racepak.

Tons 'o' ways to skin the cat.

SHit really? I thought it was metric. Now that's even easier! :bigtu:

With regards to factory temp senders, fans, etc... I believe this changed between the 1.6, 1.8 and NB models. Some have one sender for the ECU and a separate one that controls the coolant fans. Concealer is right about the MS though, it's usually wired to control everything

Moral of the story is Be aware of what you are working with before you go crazy pulling out and relocating sensors.

Personally, I would not want to eliminate the oem water temp sensor or wiring. Replacing it with an aftermarket one and doing your own wiring for it almost guarantees something in that sytem won't be as high of quality as the oem was, and your ecu is using that signal. I don't mean for fans, those could be on switches or operated by a separate sensor as is the case for the 1.6, I mean for warmup enrichments, etc.
It's one thing to get an innaccurate reading on your gauge, it's another thing for that reading to be affecting how your motor runs.
I'd leave that exactly as it is so that if I suspected something wasn't reading right, I could always verify it against the oem reading. I like redundancy...

In my case, the entire harness had to be built from scratch, all mil-spec w/ deutsch connectors. I'd trust that over 20+ year old factory crap any day.

I'm anti-Miata.net viewpoint to the extreme. Fuck everything factory. :rofl:

Fair enough, and there's some great info earlier in this thread for quality wiring resources which will help for single-wire stuff like grounds and sender wires.
I need to elevate my game in the wiring department.

So what about if you're dealing with multiple wires and want to simplify things into one plug - as opposed to how I do it now which is a single male/female connector (low quality auto parts store style) on each individual wire?

I've looked up deutsch connectors before and just gotten lost, not knowing the differences between all the different types. Then I looked at all the choices of pins, didn't know which ones went with which connectors... yikes. What series has the specs you want for automotive stuff?
Something like "ignore the rest, use this type of connector and pins, just pick how many pins you need for the speicific job" would really clear things up to a wiring rookie like me...

-Ryan

edited the above post with additional questions...

Well, honestly. I use the stock water temp gauge and sender. They work amazingly well if you do the linearity mod. There is like 50 million write ups on how to it and it costs about $2 in resistors from radioshack. I don't see the need for an aftermarket water temp sender or gauge on the miata.

I also happened to do the linearity mod on my oil pressure gauge but found it to be less useful. With temp. you know about where you need to be and small red strip will tell you what not to pass.

As for oil temp. if its before your t-stat opens, then you probably don't care anyway. You can also run a non-t stat'd sandwhich plate, or run an in-line t-stat that is outside of the sandwhich plate. All options which can get pretty complicated quick.


Pinning connectors tends to be difficult to find. A lot of the high quality pin & connector stuff are intended for manufacturing. the parts aren't expensive, but the pinning tool is usually north of $1000, some way beyond that. It sucks. SparkFun has some good stuff for the hobbyist, but most of it is not intended for automotive or high heat application.

We use these heat shrink/solder crimp connectors from Del City with the correct ratcheting crimper.

https://www.miataturbo.net/attachmen...ine=1401994771
https://www.miataturbo.net/attachmen...ine=1401994771

Ryan if your willing to wait I am working on an arduino based gauge solution that monitors oil temp, oil pressure, coolant temp, coolant pressure, voltage, and fuel. Code will contain warnings and shift light as well. Currently have the circuitry and sensor calibration equations down on paper. I have built similar circuitry and wrote programs for the lab like this so should work out. I plan to do a writeup once done.