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Rocky Mountain or Grand Rapids EIS 4000?

tonyjohnson

Well Known Member
I am considering lower end engine monitors, specifically the RMI umonitor and the GRI EIS 4000. The price gap between these lower end units and the other engine monitors is significant, prompting me to go with one of the above.

I would appreciate the input of those of you who have experience with these units, and those who have been torn as to which one to choose. Or, perhaps, thoughts on why I should go with one of the higher end units.

Thanks,

Tony Johnson
RV8A Orlando
N12TJ reserved
 
Grt Eis 4000

Tony,
I'm using the GRT EIS 4000 and really like it. Simple to use, simple to wire, easy to replace if necessary, reasonably priced for what it does. I was initially concerned that a digital RPM would be a problem... it isn't. You'll get adjusted to it after one flight. The alarm functions are very nice. Can't say anything about the Rocky Mountain unit, never tried with one.
Mark Andrews N598X
 
I have a MicroMonitor. It's nice but I wish I had gone with GRT's engine monitor because then I could easily add a graphic monitor if I so chose. The MicroMonitor is a good box and does what it does well but I do like the graphical representations of the other products. Also one drawback of the MicroMonitor is that all the temps are in Celcius! Can't be changed.
 
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micro monitor temp readings

Scott,

Thanks for the input.

RMI has just come out with an upgrade for the micro monitor that shows the degrees in F. There are some other upgraded things as well.

http://www.rkymtn.com/

Even the lower end monitors cost more than the old style gauges that Vans sells. I am wondering if the price difference is worth it? Also, the old style gauges are graphic in that they have ranges in color on their faces.

Tony
 
Stick with the GRT EIS. If in the future you decide to upgrade to the full blown EFIS, you get credit for already having it. Also, some of the newer engine monitors are offering "plug/play" replacement cables for the EIS should you decide to upgrade. For example, Dynon will be offering a nice "upgrade" kit including a patch cable for current EIS users to upgrade to the Dynon Engine monitor.

Just my 2 cents as usual!

Cheers,
Stein.
 
Eis 4000

tonyjohnson said:
I am considering lower end engine monitors, specifically the RMI umonitor and the GRI EIS 4000. The price gap between these lower end units and the other engine monitors is significant, prompting me to go with one of the above.
Tony, I don't like to think of my EIS4000 as a lower end unit but lower priced :D . I love the GRT EIS4000. I don't need to see color graphics with limit warnings on all channels. It is a real safety device. The EGT/CHT does have a bar graph display you can customize with other data (RPM/MAP/OP/OT/FP/CARB T/OAT or what every you want). Of course Greg and Sandy and company are great to deal with. Bang for buck I don't think you can beat it.

The thing you have to remember the EIS has a small display and only displays a hand full of parameters at a time, on a two line monochrome LCD screen. Also displayed info for the most part is just numbers with a few punctuation marks or units to denote what is what. This to me is not a big draw back. Being small is good and the computer monitors all parameters, displayed or not. Because displayed info is mostly numbers, you have to know what and where to look on a particular page, especially the custom pages. These pages can display any data you want. However a push of a button will display the titles of any page if you forget. The custom pages can be set up to display up to 4-8 items. There are about 14 pages of data, some are custom and some have fixed info. You can scroll thru these pages or hide them from the menu with few pushes of a button. As mentioned, the only graphical information is a EGT/CHT with a bar graph/missing segment format. There is a host of very nice features. The best is the warning of any limit exceedance, which shows up with a warning light and the respective info page popping up automatically with the critical item flashing. Another well thought out functions, "leaning" pages or max CHT rate of cooling.
http://members.aol.com/enginfosys/leanpage.htm
Last you can add 6-aux inputs to monitor custom parameters. Again the idea is you don?t have to monitor these items by looking at them on a screen, because the computer does the monitoring and lets you know if something is out of limits. Even Boeing does this with a primary engine display and a secondary display that the pilots can blank. If any secondary engine item goes into the "red" the display pops up automatically. :D

I know the new stuff is pretty with color graphics, but for utility and function you are not giving up much with the "lower end units" :eek: I am not sure what the actual cost delta is, but it is around $2000 for some units. I would consider the new color graphic displays if I was buying today, with their tempting pretty color displays, but it is still hard to beat the small/cheaper basic EIS4000. The basic EIS4000 cost $995, including 4 x EGT, 4 x CHT, RPM, oil press, oil temp, volts, flight timer. Adding Fuel flow, L&R fuel levels (5 set point capacitance senders), amps, manifold press, MAP, carb temp, fuel pressure brings it up to around $1800. Subtract $375 without the Fuel flow option, which is the highest price option. All this in one small display (and a lot of wires). The advance AF-2500 engine monitor cost $4,000!!!

Of course if you are going with GRT EFIS, than the choice is a done deal. Gregs flight EFIS is set up to combo with his grapical engine monitor. However we are talking big bucks for GRT EFIS/EIS, but I think if you have the $$ it is worth it. My whole panel cost a little more than $6,000 total: Dynon ($2,300), EIS4000 ($1700), used transponder ($300), IC200 com ($700), Garmin 195 gps ($300) and navaid autopilot ($1,100). (bargin prices I paid). Just one of those fancy EFIS boxes can cost more than my whole panel! My panel with autopilot and EFIS display is not what I would call bare bone either. My point is you can make a nice delux VFR panel for not a lot of money.

Cheers George

Image below shows typical display:
EGT/CHT bar graph Cyl #1 thru #4
EGH=1538 (F) highest egt temp (bar graph shows #2 cyl is highest)
CHH=370 (F) highest cht temp (bar graph shows 4 is highest)
RPM=2530, Manifold or MAP=25.2 (in hg)
OT / OP = 193 / 48 is oil temp (F) / oil press (psi)
Push "display" button will show lables for data fields.
This is one of 14 display pgs, incld several custom pgs, showing any combo of data you want.
eisfp3.jpg

The GRT EIS 4000 shows alll 4 EGT's and all 4 CHT's at the same time and has a program to monitor them and set them. The Rocky Mountain just shows one EGT adn one CHT at a time and you need a rotary switch to select each cylinder one at a time. Not real great for leaning and engine trouble shooting.
 
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Eis 4000

George,

Perhaps I should have referred to the EIS as a "lower cost" unit. I have heard great things about the EIS 4000. The more expensive graphic units don't seem to have any advantage over it, except for the display, which is easier to read at a glance.

I like the alarm features of the EIS, which counteracts the disadvantage of the graphic display of the more expensive units, in that it tells you when to look at the display because something is amiss.

One advantage of the EIS over the Rocky Mountain MicroMonitor is that it displays egt and cht on all four cylinders. I am wondering how important it is to have all cylinders displayed, instead of just one cylinder?

Do you find the digital display of the EIS easy to read at a glance? It seems confusing to me that only numbers appear, unless you opt to have only 3 readings per page, and descriptive letters below the numbers.

Thanks for your input,

Tony
 
go for the GRT EIS

Tony

Having all the cylinder temps is a requirement in my book. Just looking at one at a time doesn't really tell you much of a story. You can get quite a difference between EGT's depending on what you are doing. Some people say that you only need temps on this or that cylinder because that's the hot one. Well I've found that there isn't 'ONE' hot cylinder, it really depends on the conditions you are running. My hot cylinder during WOT climb is different than the one during cruise. Plus having all the temps really helps in tuning your baffles.

I have the EIS4000 and it's been really nice. At first you get alarms all the time until you get the settings sorted out. Once you figure out that you don't need all those different pages you can delete them done to just a few and your work load goes way down. Plus GRT are great to work with and you can update later on, the Dynon is also an easy update later on using all the GRT wiring. Also little cheaper than the GRT, but the display is not as big.

Cam
 
tonyjohnson said:
Scott,

Thanks for the input.

RMI has just come out with an upgrade for the micro monitor that shows the degrees in F. There are some other upgraded things as well.

Tony

Yee-haw! Finally! Thanks for point this out. Finally temps I can understand!!
:D
 
Scott (and all),

The URL for information on the Rocky Mountain microMonitor upgrade can be found at: http://www.rkymtn.com/Updates.htm

Besides having temps in (F) now, two other biggies for me were 'Percent Power Readout' and having the last 16hrs of engine data stored internally (can dump it out to EGTrends or EGView graphic software for analysis/record keeping.

Picture of upgraded unit (note temps and % power):
image002.gif


B,
 
If you decide to go with the Grand Rapids EIS, make sure it is well grounded as per the installation instructions. My display was jumping around erratically, drove me crazy until I called Grand Rapids and they told me this was almost always caused by a faulty ground. Found a loosely crimped ground connection, changed it out and the unit has worked perfectly ever since. :cool:
 
GRT viewing ease

I think you'll find that the numbers are very easy to see and assimilate in a single glance. On one of teh custom pages available, I installed RPM, Oil Temp, Oil Pressure on the top line, and Fuel Pressure, Hottest EGT, Hottest CHT on the bottom line. This is also the default page. It is quite handy.

Also, like GMCJETPILOT said, having the same experience with which cylinder is hottest in different flight modes.

If you've got some cash burning a hole in your pocket, go for the pretty graphical stuff. I would have, but am incurably thrifty... except when it comes to burning avgas :D Most importantly, buy what makes you happy.

Mark Andrews N598X

tonyjohnson said:
George,

...
Do you find the digital display of the EIS easy to read at a glance? It seems confusing to me that only numbers appear, unless you opt to have only 3 readings per page, and descriptive letters below the numbers.

Thanks for your input,

Tony
 
Rocky Mountain Micromonitor

I looked closely at both the RMI Micromonitor and the GRT EIS 4000.

I decided on the RMI box for a bunch of reasons:

- it fit into a standard avionics rack, and is easy to remove and upgrade (if necessary)
- it's display is easier to interpret than the GRT box... and in a stressful situation, that's a big benefit.
- it appears to be much easier to use.. only a couple of different display modes are used, not several.
- it's a fair bit lower cost, especially in kit form.
- it's a lot easier to wire up, especially if you want to make a removable panel.
- the RMI box looks better. That counts, doesn't it?

Yes it would be nice to have multichannel EGT/CHT automatically scanned, but my local A&P just laughed when I said that it would be nice... "on an O-320, it's overkill". If I was running a high compression engine with GAMI injectors lean of peak, then for sure.

Others will complain that the RMI box does not support fuel level sensors... this is true, but I really don't like 'god-boxes' that pack everything into them. If your engine monitor fails, then having external fuel gauges is a huge benefit. Have the engine monitor compute fuel flow, and use a seperate system for fuel level... totally redundant and fault-tolerant in my opinion.

Vern Little RV-9A
 
Rocky Mountain Micromonitor

I looked closely at both the RMI Micromonitor and the GRT EIS 4000.

I decided on the RMI box for a bunch of reasons:

- it fit into a standard avionics rack, and is easy to remove and upgrade (if necessary)
- it's display is easier to interpret than the GRT box... and in a stressful situation, that's a big benefit.
- it appears to be much easier to use.. only a couple of different display modes are used, not several.
- it's a fair bit lower cost, especially in kit form.
- it's a lot easier to wire up, especially if you want to make a removable panel.
- the RMI box looks better. That counts, doesn't it?

Yes it would be nice to have multichannel EGT/CHT automatically scanned, but my local A&P just laughed when I said that it would be nice... "on an O-320, it's overkill". If I was running a high compression engine with GAMI injectors lean of peak, then for sure.

Others will complain that the RMI box does not support fuel level sensors... this is true, but I really don't like 'god-boxes' that pack everything into them. If your engine monitor fails, then having external fuel gauges is a huge benefit. Have the engine monitor compute fuel flow, and use a seperate system for fuel level... totally redundant and fault-tolerant in my opinion.

Vern Little RV-9A
 
Rocky Mountain Engine Monitor

I have a Rocky Mountain Engine Monitor and have flown over 600 hours with it. I am very pleased with the unit and would install another one if I was crazy enough to build another airplane. It is installed in my RV6A which has a O360 A1A engine.

I agree with Vern's comments completely. For a carburetor engine a full display graphic engine monitor is rather overkill. I use mainly the fuel flow numbers when leaning out the engine in cruise also keeping an eye on the EGT.

Also I prefer to see digital numbers as it is easy to see trends such as for example the oil temperature rising in climb and going down in cruise.

I have a four position switch which allows me to look at each cylinder CHT and EGT one at a time. This is also useful if you have plug fouling on the run up so as to determine which plug is causing the problem.

Also after sales support from Ron at RMI is very good.

Barry
 
Monitor all CHTs & EGTs

FWIW, my view is that monioring all the CHTs and EGTs at the same time is almost essential. I have just fitted a new engine, the CHT spread was 80 F! With a little baffle work it is now down to 20F. If I did not have all the cylinders monitored (with an EIS 4000) I would not know what was going on.

I really like the EIS because of the BRL (Big Red Light), it flashes when any parameter exceeds the limit you have set. This means you can concentrate on flying while the box does the monitoring. My EIS cost $1150 last summer (with manifold press, carb temp, fuel press, but without fuel flow) other options can be added at any time. I have separate fuel gauges and would not hook them up to the EIS - I like to see how much gas I have. After a few hours you get to understand how the gauges lie to you.

I haven't used the RMI monitor so can't comment on it, I went with the EIS because the display is smaller, all 4 cylinder temps are displayed at once and it has the BRL. I wish it had a memory function.

Pete
 
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rocky mountain micro monitor has bad gph and map

my umonitor is showing optimistic fuel flow rates 30% low and my map is really low. i've tried to calibrate the map with engine off at the airport using the barometic pressure and still shows only 16" of pressure at full thottle (lycoming o-320). new senors or programming errors. also, any way to calibrate the other sensors. losing faith in this instrument thanks.
 
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