Hi all,

I am beginning to shop around for some guages as I'm tired of guessing approximately what my temps/pressures are.

I'm trying to decide between mechanical and electric, specifically for water temp. Now I plan to go standalone (megasquirt) this summer/fall so I will need an electric water sensor for the ems, do most people use the same sensor for the ems and their guage, or does the ems use an entirely seperate sensor? Is there a response or accuracy difference between mech and elec gauges?

Another thing is degrees of sweep. Currently I have an Autometer mechanical boost guage (full sweep), and I would like to stick with that layout but its not a requirement. Now the electrical guage of the same series an my boost guage is only 90°, which I could probably get used to but I would prefer full sweep.

 

the mechanical autometer coolant temp gauges i've seen have a huge sensor/compression fitting...it is something like an inch wide. i would stick with the 1/8npt electrical sensor. use a different sensor than the ems uses (the gauge should come with one). mount it on the back of your waterpump housing

 

the sweep is a big reason I went with the mechanical

 

Yeah I personally prefer the sweep of a mechanical. Without it is like covering up your peripheral vision.

 

For oil and water temp I prefer the SPA design dual digital readout. For me it's easier to read precisely at a glance, and it has programmable warning lights for each channel. It also only takes up one gauge pod to display both temperatures.

For oil pressure I also prefer an electronic gauge (analog display though), for a few reasons. You can have a warning light, there is one fewer fluid connection to fail and leak oil, and there is no high-pressure oil entering your cockpit area.

 

On my Turbo II, I use mechanical oil pressure and boost. For those two critical gauges (especially the oil pressure one), I'd like to have a no bullcrap reading that can be flubbed with an electric gauge. Plus, if that oil pressure gauge reads zero, then you know it's zero.

B

 

I'm wondering if I get a mechanical water temp, the water must travel through ~4' of tubing before it reaches the guage which, to me, seems like the temp could change a bit before it reaches the guage.

 

I'd suggest electrical simply because it is far easier to manage the connections to the gauge. If you go mechanical, you are limited by the tubing or the attached sender. Mechanical oil pressure and fuel pressure gauges must be installed with an isolator to be safe.

There are full sweep electrical gauges available...check AutoMeter's website.

 

I like electronic gauges for everything but boost. I like the quick reaction of a manual boost gauge. Obviously this is counteracted by a quality electronic gauge.

I have a prosport electronic and it reacts too slow for my liking.

 

There is no full sweep electric in the small Phantom style, which is what my boost guage is. I guess I could go switch to a different style for these guages, its just that having not all the same guages is untidy, IMO.

 

Well, zero at the gauge anyway. I had the compression fitting on a mechanical one fail on my race car and I lost all my oil.

 

Upgrade other gauges to match? The Phantom II line has full sweep electrical.

 

That's not how the gauge works.

The bulb (the part that's in contact with the coolant) and the line to the gauge are filled with ether (or something that smells just like it).
As the ether expands/contracts it operates the mechanism in the gauge through a diaphragm.
The worst that can happen if the line ruptures is the ether escapes and the gauge stops working...there is no coolant leak to worry about.

 

I wondered about that. If the coolant was actually going to the gauge, you'd need a return line too.

I got prosport full sweep electrical gauges. I like them, but for a N/A DD, the accuracy and response time aren't super critical.

 

Do any of you guys use the AEM electical gauges?? I like the way it has the digital read out as well as the "sweeper" guage like the wideband.

 

I picked up a Marshall full sweep electric coolant temp gauge from eBay. I'm running mechanical oil pressure, but wanted full sweep electrical for the rest, to simplify cabin routing.

It's sexy and it works awesome, and it was way cheaper than any other full sweep temp electric gauge.

 

Over 6 years of Rx-7 ownership I've seen Autometer oil pressure and water temperature electric sending units fail multiple times on my own two cars and on other cars.

 

over 20 years of running autometer mechanical gauges in at least a dozen cars I have never had oil in my car. Once I bought a used car that had them and the ferrule on the back of the gauge needed to be changed, it was slightly sweating, so .30 cents repaired that
Never had to change a temp gauge either