Airplane Altimeters in an 80?

[goschbrandon]

Ok- I searched and found nothing- has anyone put in an airplane altimeter in an 80? Maybe out of a Cessna 172 or other small plane. Or, for that matter, a roll or pitch guage? I know there's JDM and overseas OEM stuff, but I think something out of a plane would just be damn cool.

 

[RavenTai]

Aircraft altimeters are uber expensive and large, but quite accurate as long as you input the barometric pressure ever hour or so,

old school turn and bank indicators run on gyros that are powered by vacuum, more vacuum that you would want to tap the intake for, you would need a vacuum pump, newer styles can be electric but are generally have more info and more cost

not practical unless you know where some are sitting somewhere

 

[Montana Cruiser]

It wasn't just JDM Models that got the altimeter 80's 4-Runner's also had them, can be sourced from a parts yard. Then there is the JDM 80 overhead console unit, C-Dan and I think Boston Mangler have them, pretty slick but big $$

Anything coming out of a plane would be total overkill for a Cruiser ...... PERFECT

 

[Pete483]

You'd be looking at a lot of money for an aviation altimeter, not to mention they are not that small (they go back from the face more than you'd think). A pitch gauge/artifical horizon would be even more expensive. A lot of electric guages run on 28vdc or 120vac too, so that's an issue.

You might be able to find some somewhere that are not longer certified for flight, though they probably wounldn't work and still wouldn't be all that cheap.

I just use my Garmin's GPS altimeter function. It works well enough and doesn't require me to either know a benchmarked altitude or the current pressure. If you don't set the altimeter setting correctly, even an aviation altimeter that is +/-50 feet or so could be off over 1000 feet off.

I do wish that car electronics worked more like avionics where everything was standard sized and fit in racks. I don't think you average car buyer would go for that though, seeing as how as lot of new cars can't even have aftermarket steroes put in.

 

[robchad]

Aussie model 80 series have the altimeter, I have one and they pretty accurate, reads the the same as my gps reading.

 

[SUMOTOY]

Aviation Guages

I purchased a manifold pressure guage from a helo about 10 years ago, for really accurate boost measures on my turbo car tuning. Back then (probably 1960's vintage) it was around 500 used, and it's my understanding that all aviation guages sold in the US (new or old) have to be aviation certified (read: that costs money)

GPS should be just as accurate, if not more so.

Scott Justusson

 

[ginericLC]

I purchased a manifold pressure guage from a helo about 10 years ago, for really accurate boost measures on my turbo car tuning. Back then (probably 1960's vintage) it was around 500 used, and it's my understanding that all aviation guages sold in the US (new or old) have to be aviation certified (read: that costs money)

GPS should be just as accurate, if not more so.

Scott Justusson

GPS is not very accurate. An altimeter from a plane is a lot more accurate. On peaks I've been as much as 200 feet off with my GPS. I've never been less than about 38 feet off.

My dad has a Beechcraft altimeter in his LX450. His friend gave it to him. He replaced the guages in his plane for some reason. To buy it, it would have been very expensive.

I've seen add on altimeters in a wide variety of Toyotas over the years. The coolest one was in a 4Runner. I believe it was aftermarket. It slid into a little pocket mounted on the dash and when you left the vehicle you could slide it out and take it with you.

 

[jerseyfzj80]

Buy a casio or suntto watch with an altimeter on it most of them will go to 19000 feet. much cheaper and almost zero install time!!!!

 

[BLACKGOLD]

My GPS has an altimeter in it. If you dont have a GPS...get one with an Altimeter.

 

[GeoRoss]

GPS should be just as accurate, if not more so.

As has been mentioned, altitude measurement via a hand held GPS unit is not very accurate. Now if you take the time time to correct the sat signals using a second unit at a know location (w/in ~ 100 miles) you can get >cm accuracy.

 

[MoJ]

Non-aviation (sat based altimeter, not barometric) Garmin GPS units are rated at +/- 100 feet when locked to four sats. This is a general rule of thumb rating Garmin uses to avoid liability issues, ie someone tries to land a plane using their non-aviation unit. Accuracy improves of course with more satellites. My experience with my 276c has been around +/- 20 feet when I've compared it with a few airports. It does however consistently show the same altitude for a give point - for example each time I return to my driveway it's always 810ft.

 

[Pete483]

While a run of the mill Garmin or other GPS using GPS altitude is not particularly accurate, odds are it is much more accurate than a nice barometric altimeter than doesn't have the current altimeter setting.

Another problem with barometric altimeters is that cold temperatures cause them to read high. For instance, if you are at 5000 feet with the current altimeter setting in your barometric altimeter, and the temperature is 32F, your altimeter would read 5280'. This error increases with both altitude and temperature. At sea level on a 32F day, you'd read about 20', whereas at sea level on a -40F day, you'd read 50'. On top of that 5000 foot mountain on that cold of a day, your super expensive altimeter would read around 6210'. While my Garmin's screen would be moving really slow at that temperature, I'd still only have to 100ish foot error it always has.

 

[SUMOTOY]

My question would be how accurate do you need altitude to be, if you are already on the ground? GPS within 100 feet is accurate enough for using it as a tool (for what?). Altitude makes a difference to a blown machine in terms of Rressure Ratio, and IME 200feet would be accurate enough for the most finite of tuning, btdt.

We tested the altimeter in my old 4runner, and it was pretty close to what Mr. Garmin popped up. Knowing any pressure guages is accurate on how it's baselined, the triangulation electronic method will yield consistently better accuracy over time IMO.

Scott Justusson

 

[Grench]

Redneck tiltometer

old school turn and bank indicators run on gyros that are powered by vacuum, more vacuum that you would want to tap the intake for, you would need a vacuum pump, newer styles can be electric but are generally have more info and more cost

not practical unless you know where some are sitting somewhere

Or you could build a redneck version.

1. Buy a soda at McD's (or equivalent.)
2. Drink half of said soda. Put it in your factory cup holder whiile parked on a flat surface.
3. lay a protractor on the side of it.
4. Mark off about where 15 degrees is at both up and down.
5. Draw a circle around the cup at 15 degrees or so up and down from the soda line. Put one on the soda line too if you want to be fancy.
6. If the soda hits the center of the bottom line towards you, you're going downhill.
7. If the soda hits the center of the top line towards you, you're going uphill. If it exceeds it say, "yee haw."
8. If the soda hits the DS top line hang your buddy on the side as a counterweight.
9. If your lap gets wet, you're upside down.

Bottled beer works well too. Especially Bud Light. It already has markings on the side for this. Might not sit well with the local enforcement people though if you have to explain that you don't have an open container... your tiltometer is just beer based.

All scientific instruments can be calibrated with stuff you can build in your garage. Just break down the units.

 

[Grench]

Barometric altimeter

This one is a bit less redneck although I suppose you could fill it with beer if you want. I'm not sure of the specific gravity though, so you're on your own there.

1. Get a 6'section of heavy walled clear vinyl tubing and a yard stick.
2. fill half the tube with water.
3. make a U in the tube and tape the yard stick to it. Use clear box tape so you can still see it.

You now have a manometer that reads in inches of water. It is accurate enough to calibrate your vac and pressure guages. You will need to build a taller one if you want to calibrate the one on your air compressor. Put a plug in one end and you have a barometer. If you know the barometric pressure, then the changes on your barometer that are not accounted for in the barometric reading are due to altitude. If you are traveling and assume that the barometric pressure hasn't changed, then you have an altimeter.

 

[Colorado Boy-74-FJ40]

Check this out. It looks much like an aircraft altimiter. I am an Aircraft Mechanic and I believe the statement about approved altimiters is correct. I don't think you can buy an actual aircraft unit on the market. this looks good. I might even buy one
http://www.altimeters.net/altswifta...altimeters&OVKEY=car altimeter&OVMTC=advanced

 

[mnwolftrack]

You may already know this, but high end late 1980's 4Runners came with a factory altimeter/clinometer gauge set that sat on top the dashpad. It's mounting system is pretty simple and would probably fit on top a FJ dash. I have a spare gauge set, but I haven't tried installing it yet.

Also, mid 1980's Toyota 4x4 wagon Tercels had an almost identicle gauge set, however a 4WD light indicator was in place instead of the altimeter. I have a write up on my website of the install I did in my '85 pickup. It's also very easy to wire up since it's only a + and - for backlighting, and it of course looks factory. The problem with the 1990 and newer 4Runner clinometer gauge sets from Japan is that the dashboard is right hand drive in Japanese 4Runners and is sloped from one side to the other.

Here's a link to my site:

http://www.geocities.com/toyotashawn/85clinometer.html

Note that the pictures show the Tercel 4x4 Wagon gauge set with the 4WD light, but I have since installed the actual 4Runner gauge set with the altimeter. The 4WD light obviously isn't needed in an FJ, however I did find it useful in my pickup because the steering wheel exactly blocked out my view of the 4WD light in the cluster gauge by the speedo.

 

[goschbrandon]

wow- lot's of info!

Thanks for all the replies- I like the redneck versions. I have a suunto altimeter watch but, I'm just looking for something cool for the truck with the plane altimeter(still like it to work though), and i think it'd be neat to have. the 50$ unit in the link posted by Coloradoboy looks pretty nice for the money. I did find these:
http://www.aircraftspruce.com/menus/in/altimeters.html
but $$$$ is too much. I'm hoping to find a used one, but I'm thinking that the used parts market for aircraft isn't real big.

Ginericfj80- does the Beechcraft unit run off of 12V for lighting?

Maybe this is just a dead-end project, and I will have to install the redneck cupholder unit on the dash.

 

[RavenTai]

hmm that General avation stuff is much cheaper than I thought, comercial stuff is much more money,

 

[IBCRUSN]

Here is another option for an altimeter:

http://store.wagaero.com/product_info.php?products_id=12749

It is a non-TSO'd (certified) unit hence the lower price. Your other options are to check out eBay or other experimental aircraft parts vendors. Just keep and eye out for non-TSO'd units that will keep the price down. Regardless if you are looking for an accurate unit find a calibration lab and they can calibrate it for you. an additional option if you live near and airport is to talk to the local avionics shop and they may humor you and check it against their pitot/static tester. I think that's getting a little too involved for an installation in a truck.

RT,
Yeah, small piston GA is far cheaper than turbine GA and the heavies. We won't get into the ADC's here as that's just unrealistic and complex for a truck.