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I found some really usefull gauges that are used for aircraft. There are 2 that i am really interested in since they combine so many features into one gauge. First one is one gauge that can control 4 egt probes. Goes up to 1900 degrees. The second one can show both oil pressure and temp on one gauge. The only issue i can see is that they are 14v, but if they are hooked up directly to the alternator i dont see there being a problem. What do you guys think?
 

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There are no problems associated with using the guage itself. The probe for EGT is the main concern. Aircraft use EGT probes that are larger and slower to react than would be useful on a car. This makes them more reliable over time. Aircraft operate on steady power output and don't fluctuate like a car driving down the street. Even a race car will only use 100% power 50% of the time at RPMs all over the place , wherease an aircraft engine runs at 85+% 100% of the time with constant RPM 100% of the time. You need a faster reacting probe to go with the guage.
 

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Discussion Starter #5
Medpilot said:
There are no problems associated with using the guage itself. The probe for EGT is the main concern. Aircraft use EGT probes that are larger and slower to react than would be useful on a car. This makes them more reliable over time. Aircraft operate on steady power output and don't fluctuate like a car driving down the street. Even a race car will only use 100% power 50% of the time at RPMs all over the place , wherease an aircraft engine runs at 85+% 100% of the time with constant RPM 100% of the time. You need a faster reacting probe to go with the guage.
oh okay, they do sell the gauge without the probes, so im sure if i bought them separatly they would work.

here is a pic:


you can also have it show the highest temp reading by default.
 

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Take it from a licensed A&P, looks cool but you'll probably have problems getting to work correctly.

1) Aircraft electrical systems are different than automotive systems. Most small aircraft run 14V - 28V NiCad systems.

2) Cost - Aircraft components require certification from the FAA and must be installed by a licensed tech which tends to make them very expensive.
 

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The voltage range in the manual for that partuicular instrument is from 6V to 32V DC...

certs by FAA don't apply to cars...

thermal mass of K-type junction isn't the problem, it's the mass of the casing that it's mounted in; lots of people sell exposed junction K-type probes...
 

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I realize the FAA does not apply to cars...The Gage itself must be certified (STC ST01700NY) for aircraft use. This is an aerospace Gage, not automotive. Check their product listing, 4 cylinder Gage only $372.00, add another $144.00 for probes and installation hardware.

Check the schematic - "Aircraft Positive Supply 14V-28V"
 

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ive been flying for about 3 years now and love it :) but as far as guages go it would be a pretty cool thing to see in a car. If you are having a problem with the price just go to your local airport the mechs. usually have older ones sittin around. i could put a plane togther will all the exta parts laying around our little country airport.
 

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mrtwo91 said:
I realize the FAA does not apply to cars...The Gage itself must be certified (STC ST01700NY) for aircraft use. This is an aerospace Gage, not automotive. Check their product listing, 4 cylinder Gage only $372.00, add another $144.00 for probes and installation hardware.

Check the schematic - "Aircraft Positive Supply 14V-28V"
As an A&P myself and professional pilot going on 15 yrs of experience, I can also assure you that the main "down side" of this is merely the price tag. Sometimes you can get get an aircraft manufacture to sell you something direct at a reduced cost if you are willing to sign a statement that the profuct will not be sold/used/remanufactured, etc.. for aviation use. Not often, but it does happen.

On another note, any 12vt system, be it an aircraft or automotive system, is rated for 14-15vts. Your MR2 is consistantly supplying 14.7vts to all electrical systems. So does an aircraft.... it's the result of the alternator. Aircraft rate items by terms of average constant voltage output. Ie. a 12vt battery will always be a 14vt system and a 24vt battery will always be associated on a 28vt system and so fort. In automotive, things are oversimplified and ******* gear-head-anti-stupified. So a car is commonly refered to as a 12vt system even though it is no different than an aircraft system.
The type of battery, ni-cad/lead acid, has nothing to do with this. the ni-cad is designed to supply constant amprage without drop until the life is expended, then it drops rapidly. These are most common on turbine engines due to the need to keep the starter at is max potential to prevent a "hot-start" A lead acid amperage will taper down as it is expended. Anyone who has run down a battery with the starter on their car has seen this. ie;
lead acid: da-da-da-da-da---da----da----da-----da--daaaaa-klik-kkkkk;
ni-cad: da-da-da-da-da-da-da-da-da-da-da-da--da---da....klick-kk.......

Edit** just wanted to add that I looked at the instalation diagram and wanted to confirm that this unit is compatable with Both 14 and 28vt systems. If you were to add a rheostat (light dimmer), you would need to connect it to the 14vt terminal. And just to clear it up....It don't matter it's an aircraft designed guage. U can stik it in yo Karr if yant to. :battery
 

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Yea i have been looking at those ever since you sent the linkt o me....i talked to a couple electric engineers about it and they say it will work fine. THe battery has nothign to do with DC power in general.
 

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Another potential downside of aircraft guages are also the shear size of them. they usually require a 2-1/4" hole. the guages themselves are much larger than that. Pretty bulky too. But that is just a personal preference.
Tyson
 
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