Aerospace Logic CHT+EGT vs EI/JPI EMS

Aerospace Logic CHT+EGT vs EI/JPI EMS

Hey Guys,

I would really like to get a 4 cylinder EGT/CHT for my bird, but unfortunately, various maintenance costs have meant that I have less disposable income for the purpose than I would prefer.

My basic desire is simply the ability to run LOP- IE, getting enough information about my engine to reliably know that my CHT's are staying below tolerances.  Obviously the single stock EGT/CHT piper probe isn't good enough.

I was wondering what you guys thought of using basic 4 cylinder aerospace logic gauges instead of a "purpose built" engine analyzer.  It would seem to me, with the ability to automatically display the hottest cylinder EGT/CHT- the Aerospace logic gauges fit the bill.  Sure I don't get logging/historical information, and I don't get a million and one functions - but I do get what I need to know - alerts if any cylinder goes over temp (and alerts if any cylinder cools too quickly).  I also get temperature readouts to the degree (rather than to the 10s of degrees).

The reason I ask is that the Aerospace logic gauges can be had in the 600 for the pair range (on ebay)... the cheapest multibar engine monitors are 2 to 3 times that. 

I also have a friend who has the EDM-700 in his Grumman, and he's frustrated that the User interface is so 'bad' in his mind that he "never actually uses it".  I have to say, given the circumstance, the idea of a simple "your hottest cylinder is X temp" is appealing.

I'd love any feedback you guys might have-

-Scott
N4261J

Edward Cragg
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Re: Aerospace Logic CHT+EGT vs EI/JPI EMS

This looks like a reasonable compromise.

As a software interface designer myself, I can sympathize with your friend.  There isn't an instrument in our aircraft that couldn't have a better interface.  But I don't find the interface of the EDM so bad that I can't use it.  I do bring along a cheat sheet for the commands I don't use very often, though.

Regards,
Joe

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Re: Aerospace Logic CHT+EGT vs EI/JPI EMS

Edward, buy your friend's EDM-700 in exchange for something simple he can use.

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Re: Aerospace Logic CHT+EGT vs EI/JPI EMS

Do you really find the EDM-700 that worthwhile Leigh?

-Scott

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Re: Aerospace Logic CHT+EGT vs EI/JPI EMS

Just To think out-loud a bit (and clarify my position):

I should also mention that I'm interested in purchasing a fuel-flow system as well...  Fundamentally, A- I want to experiment with LOP operations in a PA-28-140... I want the fuel flow as a safety/flight planning tool.

Based on 'buy it now' prices, I could get a CHT + EGT, TSO'ed and STC'ed, for ~750 bucks, (with probes) from ebay.

Add an EI FP-5 (600) (which often pop up on ebay for ~400, and I'm looking at 1150~1350 for all.

For Comparison:

Ei-

SR-8 (CHT + EGT for all cylinders, peak detection, hottest display, no user programmable limits (and 500 is WAY too hot for the factory programmed limit): 590 + probes.  Seems kinda awkward to use (single display for CHT/EGT for 4 cylinders = 8 total displays to cycle through).  Add FP-5, and we're talking 990~1190 (FP-5 on Ebay, SR-8's don't show up there often)

US-8  (CHT + EGT for all cylinders, peak detection, hottest display, user programmable limits) 1300 w/probes.  Dual displays (CHT + EGT for current cylinder) same as AL.  A little bit more logic, almost twice the cost.  add FP-5, and we're talking 1700~1900 (again, FP-5 on ebay, US-8 via manuf).

UBG-16 (Kitchen Sink Features) - 1650w/probes.  Special deal, Over twice the cost, but FP-5 is available for an additional 260 bucks, bringing the total cost (Engine Monitor + fuel flow) to 1910. (clearly smarter than US-8)

JPI-

JPI-700 (Kitchen Sink Features.... Friend has one in his Cheetah, HATES the UI... thou I'm not sure the EI is any better.  Also have serious reservations about JPI based on stories from the RV owners community)- 1475 w/probes.  Fuel Flow available for 700 extra = 2175 total.  Does not report current Power Percentage, unlike FP-5.

Basically, UBG-16 + FP-5 looks like the runner up, but there is substantial savings to be had going AL+FP-5 and buying a couple extra tanks of fuel- Add the simpler UI (Only tells me what I need to know- am I frying my engine?), simple install, and rock-bottom prices, and I'm definitely leaning towards that route.

FWIW, My dream would be to just go ahead and buy an MVP-50, 337 it until EI gets the STC, then grandfather it in.  I love what I've heard about the MVP-50... but The more I think about it, the more I simply can't afford to blow 5k on engine instrumentation at this moment.

My other option would be to try and go for something like a Dynon engine monitor and pray to god my local FAA rep approves a 337 for it...  I think the chances of that fall somewhere between 'probably not' and 'snowball's chance in hell'... but it'd only be ~2500 and it would allow me to replace all the legacy gauges (not to mention high-pressure fuel-lines in the cockpit).

The MVP has the tremendous advantage over the using all TSOed/STCed components (instruments, etc), so I'd imagine 337 approval for it might be more forthcoming.

Anyways... that's enough rambling for me.  Again - feedback would be appreciated.

Edward Cragg
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Re: Aerospace Logic CHT+EGT vs EI/JPI EMS

Scott, yes I do.  It gives me what I need to know, the real time EGT's and CHT's allowing me to control my engine within safe limits and will display any serious deviations from normal.  I considered the fuel flow but decided that it is something that is a conseqence of how I am operating the engine rather than something to use to control it by, if you follow me.  My Arrow has a mechanical fuel flow that seems to be fairly accurate since the rate it displays falls pretty close to my actual burn on longer flights but of course the dispaly is not nearly as precise as that of the new digital systems so this might have been a factor in my decision to not add the fuel flow.

My choice of the JPI was based on recommendations of some others around here whose opinions I respect and so far I have been very pleased with it.  I am sure others are just as happy with the competitive units so lets be glad that there is a choice, keeps the prices reasonable and the service better. 

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Re: Aerospace Logic CHT+EGT vs EI/JPI EMS

I also own a PA28-140.  I am looking to add the Aerospace duel fuel tank gauges.  If they are as accurate as claimed that would be great (to one tenth of a gallon.)   Plus, I was going to get the EI 4 cylinder EGT/CHT.  But if you were satisfied with your 4-cylinder aerospace logic gauges I might go with that.
How did it work out for you?

‘70 Cherokee PA28-140

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Re: Aerospace Logic CHT+EGT vs EI/JPI EMS

I'd be very surprised if you can operate LOP with a carburetor.  Fuel distribution is not nearly as uniform between cylinders as with fuel injection, so typically one cylinder starts to starve and misfire while another is still ROP.

I have the EDM700 (IO360) and to use it for LOP operations, but consider the EDM700 to have its most value for early identification of problems.  I had noticed recent periods in which #4 egt would pop up for a few minutes, then back down again.  Downloading the data revealed it had been happening in several flights where I did not notice it.  I asked the mechanic to take a close look at #4 at the last oil change and he found that the plug wire was starting to wear badly.

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Re: Aerospace Logic CHT+EGT vs EI/JPI EMS

I bailed on the EDM and am going with the Aerospace Logic 4 probe EGT and the digital fuel guage as well. It looks as though you have to remove the old needle fuel guages to use the digital, but no problem.

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Re: Aerospace Logic CHT+EGT vs EI/JPI EMS

Edward,

I have a UBG-16 and a JPI fuel flow (would be better to have gotten both from the same vendor so they'd talk to each other but...).

I fly a warrior -161.  Honestly, I am probably doing it wrong but I can't seem to get lean of peak.  I lean until I get power drop-off and sometimes try to go until I get peak.  sometimes the EGT indicates a drop but I don't get the peak alarm.  Anyway, I lean until it seems to drop or get rough then richen slightly.  Then I set power by the furl flow. 

So, I could easily live w/o the EGT I guess since I'm not really setting x degrees LOP.  The CHT is nice to have and your AL CHT idea may be the inexpensive way to go, but my primary power management tools are my ear, the fuel flow and the tach.

I did pull out a GEM602 (no numbers, just the graph) to put the UBG in if anyone wants to buy it.

Tim Morrison
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Re: Aerospace Logic CHT+EGT vs EI/JPI EMS

Tim,
What do you want for the EDM 600?
>Mike<

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Re: Aerospace Logic CHT+EGT vs EI/JPI EMS

MikeL,

Sent you an e-mail (I think) from the site.

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Re: Aerospace Logic CHT+EGT vs EI/JPI EMS

I am about to install the Aerospace Logic volt/amp gauge.  I called Aerospace in Canada and spoke with someone named Shane.  He said he is one of the owners.  That’s a pretty good recommendation – when you can talk to one of the owners on the phone.

‘70 Cherokee PA28-140

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Re: Aerospace Logic CHT+EGT vs EI/JPI EMS

I have been using the Aerospace Logic EGT for about 2 years in my Archer. The unit has been flawless since installed. As for LOP I was able to run LOP with the unit, but I only tried it above 10,000 feet.

Mike

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Re: Aerospace Logic CHT+EGT vs EI/JPI EMS

I have run into Aerospace Logic long before they were able to complete their STC + application and decided to install four of their units to replace the PA28-140 cluster: Fuel Gauge, EGT, Oil Pressure and Temp, Ruel Pressure and Amp. That was about all they had at the time.

All units have been performing flawlessly. Particularly the Dual Fuel Gauge is very impressive: precise to one gallon: I had the unfortunate occasion to try it!

Having built a new panel I purchased the CHT as well which has not been tried yet; however, I am not concerned. I wish they would come up with a Carburetor Temp Gauge: I have an extra hole in the panel that is occupied by a useless Hobbs Meter.

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Re: Aerospace Logic CHT+EGT vs EI/JPI EMS

Edward Cragg Wrote:
-------------------------------------------------------
> Hey Guys,
>
> I would really like to get a 4 cylinder EGT/CHT
> for my bird, but unfortunately, various
> maintenance costs have meant that I have less
> disposable income for the purpose than I would
> prefer.
>
> My basic desire is simply the ability to run LOP-
> IE, getting enough information about my engine to
> reliably know that my CHT's are staying below
> tolerances.  Obviously the single stock EGT/CHT
> piper probe isn't good enough.
>
> I was wondering what you guys thought of using
> basic 4 cylinder aerospace logic gauges instead of
> a "purpose built" engine analyzer.  It would seem
> to me, with the ability to automatically display
> the hottest cylinder EGT/CHT- the Aerospace logic
> gauges fit the bill.  Sure I don't get
> logging/historical information, and I don't get a
> million and one functions - but I do get what I
> need to know - alerts if any cylinder goes over
> temp (and alerts if any cylinder cools too
> quickly).  I also get temperature readouts to the
> degree (rather than to the 10s of degrees).
>
> The reason I ask is that the Aerospace logic
> gauges can be had in the 600 for the pair range
> (on ebay)... the cheapest multibar engine monitors
> are 2 to 3 times that. 
>
> I also have a friend who has the EDM-700 in his
> Grumman, and he's frustrated that the User
> interface is so 'bad' in his mind that he "never
> actually uses it".  I have to say, given the
> circumstance, the idea of a simple "your hottest
> cylinder is X temp" is appealing.
>
> I'd love any feedback you guys might have-
>
> -Scott
> N4261J

Hi Scott-

I promise to keep my salesman's hat "on the rack" as it should be here on an informational forum but I do want to make a few critical points in regards to the engine monitor arena for this reason. I will present some often-unconsidered UBG-16 characteristics that are not found on other engine monitors.

Much of the following is direct quotes from EI's staff engineer and owner, Ron Robert's publication "The Pilot's Manual for Leaning and Diagnosing engine Problems". http://www.buy-ei.com/The_Pilots_Manual_by_EI.htm

A great engine analyzer can be the most effective tool for avoiding engine problems and adding a significant level of safety to any flight. If an analyzer only displays engine data and requires the pilot to do the majority of the analysis, that pilot may be sadly disappointed in the engine analyzer when an unexpected problem arises. A great engine analyzer should automatically find engine problems for the pilot and assist in proper operation of the engine to avoid engine problems in the first place! The following features are what make any single engine analyzer a great analyzer.

A great analyzer automatically collects and analyzes engine data and displays a warning the second a problem occurs. - An engine analyzer that is only "good" comes from the first level of technology. It has a bar graph, to show current EGT's and CHT's. Also, it collects engine data and provides a method of downloading the data to a computer for later review of graphs, charts, and numbers to detect problems that may be developing.

The second level of technology in engine diagnostics is to let a computer program pour over the engine data in order to automatically find any problems.

The third level of technology is to provide programmed parameters so the computer can be customized for each of the engine's cylinders. This allows for much more accurate analysis.

The fourth level of technology is to put the computer in the aircraft and analyze the data in "real" time as it is collected from the analyzer. Finding problems early can significantly reduce engine damage. The fifth level of technology is to put the entire computer program into the engine analyzer and get rid of the computer.

The UBG-16 is the only engine analyzer that is fifth level technology, with three on-board microprocessors to analyze engine data as it is collected. The UBG-16 quite plainly looks and analyzes engine data in the same manner an engineer does: it looks for trends and deviations from normal operating levels. The UBG-16 has 34 programmable parameters to allow automatic engine analysis to be customized for each cylinder on an engine. The UBG-16 will automatically detect and alert the pilot of any developing engine problems in seconds rather than weeks or even months. The UBG-16 is also the only engine analyzer that allows you, the engine operator, to define the graphical scale in terms of temperatures per segment to match your engine's normal operational envelope.

The part I would say I love the most about the UBG-16 is the graph it provides to display long term trends. An engine analyzer which is merely "good" provides a bar graph display of an engine's CHT's and EGT's. But because the exact height of each of the bars for each cylinder is not easily remembered, it will be difficult to spot trends in the early stages. A "great" engine analyzer can store offset data for each cylinder in long-term memory. This offset data can be then displayed in a "normalized" graph of the engine's current operating temperatures. If all of the engine's cylinders are healthy, the bar graph will display columns that are of the same height. If a cylinder develops a problem, that cylinder's column of bars will be higher or lower than the others. I know of only two engine monitors on the planet that will archive this "normalized" graph once power has been turned off. Consequently, the other analyzers on the market do not have the ability to represent trends beyond their current flight. One is the UBG-16 and one is the MVP-50 system still in the certification process.

Another key feature that is unique to the UBG-16 is its fuel/air mixture profile mode. In this mode the bar graph display shows how close all of the cylinders are to reaching peak at the same mixture setting.

The UBG-16 was designed to be one of the most valuable tools that can be purchased for an aircraft. The UBG-16 has some advanced features every pilot should consider. These features have some real safety and money savings benefits that should be considered prior to the investment of another engine analyzer.

Thanks for listening.

Mathew Sharp
Sales/Technical Support
Electronics International Inc
63296 Powell Butte Hwy
Bend, OR 97701
877-318-6060 ext 190
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Re: Aerospace Logic CHT+EGT vs EI/JPI EMS

OK then Mathew while the subject is open.

I have had the UBG for a while now.  Not sure I'm really getting the maximum use out of it with a relatively small, carburated engine etc.

One thing I am noticing is that I pull back the mixture a bit and the EGT seems to keep climbing for quite a while after I've stopped moving it.  So to get the EGT to actually drop off I have to go very slowly or, what I end up doing is leaning until power drops off quite noticeably, at which time I MAY be seeing an EGT drop but not necessarily.

There was some heated discussion a while ago about fast vs slow probes.  I have your standard probes (slow I guess) and am now wondering if this long response to the mixture pull is due to that or is that really expected?

Also, often I see the EGT drop off (I it's showing the highest probe?) but don't get the PEAK alarm.  I sometimes get it later.

Tim Morrison
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Re: Aerospace Logic CHT+EGT vs EI/JPI EMS

Tim Morrison Wrote:
-------------------------------------------------------
> OK then Mathew while the subject is open.
>
> I have had the UBG for a while now.  Not sure I'm
> really getting the maximum use out of it with a
> relatively small, carburated engine etc.
>
> One thing I am noticing is that I pull back the
> mixture a bit and the EGT seems to keep climbing
> for quite a while after I've stopped moving it.
> So to get the EGT to actually drop off I have to
> go very slowly or, what I end up doing is leaning
> until power drops off quite noticeably, at which
> time I MAY be seeing an EGT drop but not
> necessarily.
>
> There was some heated discussion a while ago about
> fast vs slow probes.  I have your standard probes
> (slow I guess) and am now wondering if this long
> response to the mixture pull is due to that or is
> that really expected?
>
> Also, often I see the EGT drop off (I it's showing
> the highest probe?) but don't get the PEAK alarm.
> I sometimes get it later.

Before I answer this I would like to ask you several questions.

1.  How long does it take you to lean the engine from full rich to your cruise mixture?

2.  How far down the exhaust tubes are your probes?

3.  Are you entering the "lean" mode prior to leaning the mixture?


Mathew

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Re: Aerospace Logic CHT+EGT vs EI/JPI EMS

Mathew Sharp Wrote:

>
> Before I answer this I would like to ask you
> several questions.
>
> 1.  How long does it take you to lean the engine
> from full rich to your cruise mixture?

Maybe a minute or two...  Been trying to go slower lately and let the temps finish climbing.

>
> 2.  How far down the exhaust tubes are your
> probes?

Per your company's recommendation.  In fact, when I had it installed, (replacing a GEM602), the exhaust had to be sent out for welding to move the old probe locations to the ones EI insisted on.

>
> 3.  Are you entering the "lean" mode prior to
> leaning the mixture?

Yes.
>
>
> Mathew

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Re: Aerospace Logic CHT+EGT vs EI/JPI EMS

I still can't imagine carb guys trying to run LOP.

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Re: Aerospace Logic CHT+EGT vs EI/JPI EMS

Yes, it is said that carb'd engines are less likely to run smooth LOP but at todays fuel prices it's certainly worth a try.  I'm trying to operate my Warrior as efficiently as possible and am truing 110-115 on 7 gph.  I replaced the GEM with the UBG so I could get MP and carb temp in the box so as to have as much info on my power setting as possible and maybe use the carb heat technique.  Maybe eventually I will make full use of all that info.

The Lycoming manual says you can run AT peak.  LOP isn't much more efficient than peak from a strictly fuel flow/HP standpoint.   

So, honestly I find my fuel flow a more useful instrument since I lean till power drop off (EGT's still climbing until the sound has dropped considerably, hence my question to Mathew Sharp) is very noticeable or I get the peak flash (haven't brought myself to pull back farther than that but by then the temp HAS shown a drop) then adjust power for the fuel flow.

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Re: Aerospace Logic CHT+EGT vs EI/JPI EMS

Happy New Year Gang!



Mr. Morrison-

When an EGT goes from a full rich to a “peak”, I would expect a 2-300 degree temp rise before a  “peak” occurs.  Are you seeing this?  If leaning only takes you a 2-3 minutes you may need to make a bit smaller mixture adjustments and allow a bit more time.  See if you can determine how many degrees your leanest EGT changes prior to a peak occurring. If you can do this you're leaning at the best rate.

With a carbureted engine you may not be able to achieve a completely LOP condition (on all cylinders) prior to the engine running rough.   However I have seen some cases where a carbureted engine will be able to run LOP on some cylinders and ROP on the others.  The most common engines that I have seen this on though is an O-470 with a pressure carb.  Your experiences may be different.

The important part here to remember is that your engine should not be ran AT peak on any given cylinder with-out you being aware of it. If you choose to run at peak you will need to keep the power below 65-75% depending on the engine. 

Usually on a carbureted engine we will really only be interested in the leanest two cylinders. The rest don’t usually peak until the “roughness” comes.  So really all we have to decide is where we want to run our leanest EGT referenced to it’s peak. This can be on the rich side or it might be on the lean side as discussed.

What I like to do with the UBG-16 is to adjust the graphical resolution so that on my leanest EGT the column is completely maxed out at peak on that EGT.  This way I can approximate how far from peak I am at a glance on my leanest operating cylinder.

As a side note; EI’s UBG-16 is the only monitor on the planet that will allow for the viewing of a mixture “profile” to map the fuel/air distribution on the engine. 

Let me know what you find out and please let me know if you have any questions.

Sincerely,

Mathew Sharp

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Re: Aerospace Logic CHT+EGT vs EI/JPI EMS

Mathew Sharp Wrote:
-------------------------------------------------------
> Happy New Year Gang!
>
>
>
> Mr. Morrison-
>
> When an EGT goes from a full rich to a “peak”, I
> would expect a 2-300 degree temp rise before a
> “peak” occurs.  Are you seeing this?  If leaning
> only takes you a 2-3 minutes you may need to make
> a bit smaller mixture adjustments and allow a bit
> more time.  See if you can determine how many
> degrees your leanest EGT changes prior to a peak
> occurring. If you can do this you're leaning at
> the best rate.

My question was, why does it take what seems like a long time (15-sec or more from the time I stop pulling the mixture for the EGT to stop climbing?  Is that expected?  Is it because I don't have the fast probes?

Not sure what you mean by "if I can determine...".  Are you saying if I go to fast I'll get the peak but not see the change?

>
> With a carbureted engine you may not be able to
> achieve a completely LOP condition (on all
> cylinders) prior to the engine running rough. 
> However I have seen some cases where a carbureted
> engine will be able to run LOP on some cylinders
> and ROP on the others.  The most common engines
> that I have seen this on though is an O-470 with a
> pressure carb.  Your experiences may be
> different.

the other question I was asking was about what constitutes determining PEAK in the UBG.  I have been pulling back till I see the temp (which one gets displayed in the LEAN mode?) drop a bit but don't get the PEAK message necessarily at this point.

>
> The important part here to remember is that your
> engine should not be ran AT peak on any given
> cylinder with-out you being aware of it. If you
> choose to run at peak you will need to keep the
> power below 65-75% depending on the engine.

I am seeing fuel flow drop to below 7gph during this exercise and per the APS guys formula that's 65%.
 
>
> Usually on a carbureted engine we will really only
> be interested in the leanest two cylinders. The
> rest don’t usually peak until the “roughness”
> comes.  So really all we have to decide is where
> we want to run our leanest EGT referenced to it’s
> peak. This can be on the rich side or it might be
> on the lean side as discussed.
>
> What I like to do with the UBG-16 is to adjust the
> graphical resolution so that on my leanest EGT the
> column is completely maxed out at peak on that
> EGT.  This way I can approximate how far from peak
> I am at a glance on my leanest operating cylinder.
>
>
> As a side note; EI’s UBG-16 is the only monitor on
> the planet that will allow for the viewing of a
> mixture “profile” to map the fuel/air distribution
> on the engine. 
>
> Let me know what you find out and please let me
> know if you have any questions.
>
> Sincerely,
>
> Mathew Sharp

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Re: Aerospace Logic CHT+EGT vs EI/JPI EMS

My question was, why does it take what seems like a long time (15-sec or more from the time I stop pulling the mixture for the EGT to stop climbing? Is that expected? Is it because I don't have the fast probes?

I would say that with any mixture adjustments a carbureted engine would require some time to stabilize after the adjustment is made.  Also the linkage actuating the carburettor mechanisms will obviously control the amount of fuel drawn into the airstream and untimately effect cobustion.  The linkage variable will likely have a  large contribution to how long the stabalization takes.  The atmospheric conditions prevailing and power settings will also have effects. 

The probe question I really do not feel is pertinent here, we really only created a “fast” probe due to “creative” marketing on the part of our competition. The standard “P-110” probe, at 1.5” down from the flange, is literally going to be in the blue flame coming out of the engine.  The probe can’t help but to respond fast.  In fact, it will likely be glowing red-hot.  I am not an engineer so I can’t tell you for sure what the exact heat transference rate is.


Not sure what you mean by "if I can determine...". Are you saying if I go to fast I'll get the peak but not see the change?

What I meant was literally see if you can determine how just many degrees your leanest EGT changes prior to a “peak” occurring typically.  For you to determine this you will have to lean on the slow side of what is normally required.  As an operator I would want to record this benchmark for future analysis.  If you can determine this I know your leaning slow enough.  You really want to avoid what we like to call “the big pull”.  If you make large mixture adjustments in this fashion you could miss the peak all together. You really do have to allow the engine to respond to the control inputs, realizing each aircraft will be different.


the other question I was asking was about what constitutes determining PEAK in the UBG. I have been pulling back till I see the temp (which one gets displayed in the LEAN mode?) drop a bit but don't get the PEAK message necessarily at this point.
I am seeing fuel flow drop to below 7gph during this exercise and per the APS guy’s formula that's 65%.


The way you want to use the “Lean” mode on the UBG-16 is as follows:
For “Rich of Peak” operations enter the “Lean” mode before begin to lean your engine (full rich).  Make controlled mixture adjustments until the “LEAN” indication in the lower left window changes to “PEAK”.  Once an EGT “peaks” the UBG-16 will acknowledge this by flashing the cylinder number (top of the display).  For “Rich of Peak” operations you now stop leaning and double click the “mode” switch to the left.  The UBG-16 will then display how many degrees below peak you are on your leanest cylinder.  Then you richen the mixture, walk the negative number back to peak, which would be zero, and then continue richening until your desired mixture is achieved on the rich side of peak.  The UBG-16 is not concerned about the literal change in fuel flow. Note: if you lean to fast and your see more than one cylinder number at the top of the display flashing, more than one cylinder reached a peak and is now LOP.

Does that make sense?

Matt

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Mathew Sharp
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Re: Aerospace Logic CHT+EGT vs EI/JPI EMS

and for LOP the procedure is the same except for what direction to move the knob after the PEAK flashes I assume?

Only mentioned the fuel flow to point out that if I am hitting peak, i am  at or below 65% where supposedly that's OK.

Tim Morrison
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