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Is the JPI 800 to 930 upgrade worth it


Chris B

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I am looking to buy a plane (C brand) that currently has a JPI-800.  The seller also has a 930 that he bought last year with the intention of installing it but ended up deciding to sell the plane for something bigger.

Anyway, assuming I could get a good price on it, do you think it would be worth the upgrade?  The 800 has oil pressure (I think), oil temp, fuel flow, maybe more.  

I know the original fuel gauges are not all that accurate but he does have a Shadin Fuel computer in addition to the 800 which he says is very accurate.  It seems that all the 930 would bring to the table is more accurate fuel gauges, a cooler display, and the possibility to clean up the right side of the panel.

Am I missing anything?

The logical side of my brain is saying to save the money and put it towards gas to fly the hell out of it.

Thoughts? 

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42 minutes ago, Chris B said:

I am looking to buy a plane (C brand) that currently has a JPI-800.  The seller also has a 930 that he bought last year with the intention of installing it but ended up deciding to sell the plane for something bigger.

Anyway, assuming I could get a good price on it, do you think it would be worth the upgrade?  The 800 has oil pressure (I think), oil temp, fuel flow, maybe more.  

I know the original fuel gauges are not all that accurate but he does have a Shadin Fuel computer in addition to the 800 which he says is very accurate.  It seems that all the 930 would bring to the table is more accurate fuel gauges, a cooler display, and the possibility to clean up the right side of the panel.

Am I missing anything?

The logical side of my brain is saying to save the money and put it towards gas to fly the hell out of it.

Thoughts? 

Well the 800 and 930 are much different size for one... is there a plan for where it fits in the panel or do you mean he has a 900?

The biggest difference is that the 930 (or 900) is certified as primary engine instruments so you can get rid of the old gages.  The 800 is not, so you need to keep the old C engine gages working regardless of how nice your digital display works.  Also, the fuel gages may work better with the 800 or 900, but if you actually want them real accurate you need the new fuel level sensors as well which can work with the jpi products.

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Nearly everyone here are fans and proponents of the stand-alone 930.  I certainly understand the rationale behind that.

I have a 730 in my M20C (same as the 830 but without MP and rpm).  I like having the redundancy to the factory instruments, and the accuracy of the digital JPI.  To me, that’s the best of both worlds.

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Do note that the 930, being a primary instrument replacement, is pre-programmed for a specific airframe / powerplant. This should help you in negotiating a good deal on it. You can always keep it in a box till something it can replace fails. This will likely assure no failures of that kind. I'd take it.

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On 2/8/2021 at 11:17 PM, Ragsf15e said:

Well the 800 and 930 are much different size for one... is there a plan for where it fits in the panel or do you mean he has a 900?

The biggest difference is that the 930 (or 900) is certified as primary engine instruments so you can get rid of the old gages.  The 800 is not, so you need to keep the old C engine gages working regardless of how nice your digital display works.  Also, the fuel gages may work better with the 800 or 900, but if you actually want them real accurate you need the new fuel level sensors as well which can work with the jpi products.

I have an EDM830 in my 67F....are the fuel level sensors typically updated when an EDM830 is installed?  I've noticed my fuel burn is within .2 to.3 gallons after a long flight and a refuel so they're very accurate.  I've considered upgrading to the EDM900 to gain the advantage of primary engine instruments and forego the old analog cluster....but curious about overall install and associated costs.

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The 930 is a great unit. I have mine on the pilot's side, in my scan. I had all the factory engine gauges removed, which helps make space. As someone pointed out, one major difference between the units is that the 930 if properly installed is certified as primary for all the engine gauge functions except vacuum. The accuracy of the fuel gauges is great, but it depends very much on the fuel senders. If you have the old factory senders and do not replace them, the readout will be as erratic as the factory senders. I used to have mine rebuilt, but it seemed that needed to be done about every five years. You can replace them with CiES senders and cure that problem, but not inexpensive. The JPI may have to be sent to JPI if it is one of the older units that were set up to work only with frequency fuel senders. You may have to return it to JPI anyway, to get it set up for your aircraft, as someone said, it needs to have your particular aircraft with its redlines loaded into it. When the unit starts up it annunciates your engine model, i.e. TSIO-306-LB and your aircraft model, i.e. M20K 231. 

 

large.gallery_325_387_28818.jpg.de73eabcfd763813e0753c02d856f6b8.jpg

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1 hour ago, Sheriff23 said:

I have an EDM830 in my 67F....are the fuel level sensors typically updated when an EDM830 is installed?  I've noticed my fuel burn is within .2 to.3 gallons after a long flight and a refuel so they're very accurate.  I've considered upgrading to the EDM900 to gain the advantage of primary engine instruments and forego the old analog cluster....but curious about overall install and associated costs.

Not necessarily.  The 930 works with both the old and new types.  I have a 930 with old senders and it’s been very accurate for the 5 years I’ve had it.  So the old ones can work. Some people have trouble with them.  The newer digital ones are supposed to be very accurate and last longer but I wouldn’t go taking apart the fuel tank if the old ones are working.

Really you have 2 independent fuel indications... the tank sensors and the fuel used/remain indication which is based off the fuel flow sensor.  That requires careful calibration of “k” factor.

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16 minutes ago, Ragsf15e said:

Not necessarily.  The 930 works with both the old and new types.  I have a 930 with old senders and it’s been very accurate for the 5 years I’ve had it.  So the old ones can work. Some people have trouble with them.  The newer digital ones are supposed to be very accurate and last longer but I wouldn’t go taking apart the fuel tank if the old ones are working.

Really you have 2 independent fuel indications... the tank sensors and the fuel used/remain indication which is based off the fuel flow sensor.  That requires careful calibration of “k” factor.

Well, it is true the 930 works with both the old and new types, but older 930s have to go back to the factory and get updated in order to do that. As shipped, they only worked with the older frequency senders. That was the case back in '09 when I bought mine, EI had come out with new digital senders, I asked both EI and JPI if they would work with the JPI, I got "no" from JPI and "maybe, it is up to your installer" from EI. It turned out that some circuitry had to be installed if the digital senders were going to work. Since then JPI has changed the 930. So if it is an older JPI it probably needs to go back to JPI so the resistance senders will work. There is a long thread on this somewhere, @gsxrpilot was the pioneer on this as I recall, getting the JPI to work with resistance senders. Now it is easier, but still requires those older units to be modified.

It is true that the 930 readouts are more accurate than the various factory gauges. A 10 rpm change on a factory gauge won't move the needle enough to see it, but you will get a direct, numeric readout on the 930, i.e. 2710 RPMs instead of, say 2700.  Same for the other readouts. But the readouts are only as accurate as the sensor signal in. Many of the sensors get replaced when the 930 is installed, but not the fuel senders. Whatever you have, stays unless you replace the senders.

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Personally IMO the 930 is too big to fit in a C panel without putting it largely out of view off to the right. The warning lights to draw your eyes to the right side of the panel for an issue don't nearly cut it IMO. The 900 is a much better fit than the 930 and few have the prime panel space to fit the 930 in clear. The obvious exception above is John's panel which is an excellent layout and exactly what you want to be aspiring too. 

Once you become proficient is using an modern engine analyzer you won't want to fly without. They have the capability of alerting a knowledgable pilot that there is a problem before it progresses to something catastrophic.  

It was the case you couldn't buy 930 without all sensors to go with it, so it males little sense not to use them. Although you could reuse the EGT and CHT probes, (except for putting a new CHT probe where the existing OEM probe is), at the very least the harness should be replaces to provide a trouble free installation for some time.

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17 minutes ago, jlunseth said:

Well, it is true the 930 works with both the old and new types, but older 930s have to go back to the factory and get updated in order to do that. As shipped, they only worked with the older frequency senders. That was the case back in '09 when I bought mine, EI had come out with new digital senders, I asked both EI and JPI if they would work with the JPI, I got "no" from JPI and "maybe, it is up to your installer" from EI. It turned out that some circuitry had to be installed if the digital senders were going to work. Since then JPI has changed the 930. So if it is an older JPI it probably needs to go back to JPI so the resistance senders will work. There is a long thread on this somewhere, @gsxrpilot was the pioneer on this as I recall, getting the JPI to work with resistance senders. Now it is easier, but still requires those older units to be modified.

It is true that the 930 readouts are more accurate than the various factory gauges. A 10 rpm change on a factory gauge won't move the needle enough to see it, but you will get a direct, numeric readout on the 930, i.e. 2710 RPMs instead of, say 2700.  Same for the other readouts. But the readouts are only as accurate as the sensor signal in. Many of the sensors get replaced when the 930 is installed, but not the fuel senders. Whatever you have, stays unless you replace the senders.

They still pretty much go back to JPI for any issue, including firmware update.  I sent mine back last year to get it updated.  Probably only 2 weeks, but yes, it’s not serviced in the field.

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8 minutes ago, kortopates said:

Personally IMO the 930 is too big to fit in a C panel without putting it largely out of view off to the right. The warning lights to draw your eyes to the right side of the panel for an issue don't nearly cut it IMO. The 900 is a much better fit than the 930 and few have the prime panel space to fit the 930 in clear. The obvious exception above is John's panel which is an excellent layout and exactly what you want to be aspiring too. 

Once you become proficient is using an modern engine analyzer you won't want to fly without. They have the capability of alerting a knowledgable pilot that there is a problem before it progresses to something catastrophic.  

It was the case you couldn't buy 930 without all sensors to go with it, so it males little sense not to use them. Although you could reuse the EGT and CHT probes, (except for putting a new CHT probe where the existing OEM probe is), at the very least the harness should be replaces to provide a trouble free installation for some time.

I have to disagree.  I have a 930 to the right of my radios and it’s definitely in my field of view.  It’s a Mooney, not a 747!  I’m basically shoulder to shoulder with the copilot and it’s directly in front of her.  I do agree the “remote alert display” isn’t that useful, but the 930 is plenty big on the right.

A 900 is smaller and should be on the left.

D6920799-AC66-4B35-8C7B-04B178A2D312.thumb.jpeg.72a4bc73179d627d25867135853ee1ff.jpeg

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59 minutes ago, jlunseth said:

Well, it is true the 930 works with both the old and new types, but older 930s have to go back to the factory and get updated in order to do that. As shipped, they only worked with the older frequency senders. That was the case back in '09 when I bought mine, EI had come out with new digital senders, I asked both EI and JPI if they would work with the JPI, I got "no" from JPI and "maybe, it is up to your installer" from EI. It turned out that some circuitry had to be installed if the digital senders were going to work. Since then JPI has changed the 930. So if it is an older JPI it probably needs to go back to JPI so the resistance senders will work. There is a long thread on this somewhere, @gsxrpilot was the pioneer on this as I recall, getting the JPI to work with resistance senders. Now it is easier, but still requires those older units to be modified.

It is true that the 930 readouts are more accurate than the various factory gauges. A 10 rpm change on a factory gauge won't move the needle enough to see it, but you will get a direct, numeric readout on the 930, i.e. 2710 RPMs instead of, say 2700.  Same for the other readouts. But the readouts are only as accurate as the sensor signal in. Many of the sensors get replaced when the 930 is installed, but not the fuel senders. Whatever you have, stays unless you replace the senders.

If I remember correctly the old sensors were resistive and the new ones frequency.

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17 minutes ago, LANCECASPER said:

If I remember correctly the old sensors were resistive and the new ones frequency.

 

Just now, jlunseth said:

You might be right, not an electronics guy, but I thought I just read something the other way around???

CIES supports both the original resistive mode for compatibility and the more precise frequency mode. It was JPI's support for newer frequency mode technology that led me to upgrade to my JPI-900 with new CIES fuel senders in frequency mode.

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1 hour ago, Ragsf15e said:

I have to disagree.  I have a 930 to the right of my radios and it’s definitely in my field of view.  It’s a Mooney, not a 747!  I’m basically shoulder to shoulder with the copilot and it’s directly in front of her.  I do agree the “remote alert display” isn’t that useful, but the 930 is plenty big on the right.

A 900 is smaller and should be on the left.

Yeah, the problem with the Remote Alert Display is that it is there in case the main unit fails, but most of the failure modes also fail the RAD. For example, if you lose the alternator and have to switch the Master off there is no current at all to the panel and the RAD goes dark along with the main unit. But then the same thing would happen to your electrical factory gauges. I had a problem when I had my 930 modified to use with the CiES sensors where the "autodim" function would dim the panel to black and it could not be recovered. The RAD also dimmed to black. As far as I can tell, the only thing the RAD does is continue working if the JPI screen would fail, but if the JPI unit as a whole fails, i.e. the chip stops working for whatever reason, I doubt that the RAD will continue on. I have never had that happen, it is a very dependable unit aside from that autodim problem since cured. The RAD is required for the JPI to act as primary.

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2 hours ago, kortopates said:

Personally IMO the 930 is too big to fit in a C panel without putting it largely out of view off to the right.

I took the OPS question that he OP was buying a brand C plane not a C model Mooney. :)  I think one that rhymes with Says-nah.  And the question was the merits of JPI versus legacy round dial gauges.  To that end I prefer the compactness, resolution and accuracy of the JPI over the round dials.  I will say the JPI has changed the way I fly...for the better. 

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3 hours ago, Ragsf15e said:

I have to disagree.  I have a 930 to the right of my radios and it’s definitely in my field of view.  It’s a Mooney, not a 747!  I’m basically shoulder to shoulder with the copilot and it’s directly in front of her.  I do agree the “remote alert display” isn’t that useful, but the 930 is plenty big on the right.

A 900 is smaller and should be on the left.

D6920799-AC66-4B35-8C7B-04B178A2D312.thumb.jpeg.72a4bc73179d627d25867135853ee1ff.jpeg

Fair enough, I won't disagree with you when flying VFR. But when flying IFR, widening the scan to include the GPS in the center stack is pretty much the practical limit. I don't think the 900 fonts are really much smaller than the 930's, but I'd say the 930 devotes much more real estate to separating the individual sensors; especially EGT & CHT which I think is more personal preference than anything else. But the 930 does have every sensor value in a easily readable font as opposed to the 900 with smaller fonts some sensors with a scrolling status that uses the larger font.  I actually use mine from the right seat and can see it fine, but my scan is limited to what you see in the pict.

Panel.jpeg

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7 minutes ago, Sheriff23 said:

Does JPI ever run a trade-in upgrade program similar to some of the trade in programs to upgrade from a GNS-430W to a IFD or a GTN?  I haven't seen any trade-in/upgrade programs for the JPI yet.

They offered me a deal on upgrading from a 900 to a 930.    

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If you are hand flying in IMC the scan is narrow. You can't afford to have eyes off the six pack instruments, or their digital equivalent, for more than a few seconds, and no time at all if in turbulence. If you are flying with an AP then your scan can be more relaxed, and definitely should include at least the moving map to make sure you are on the course you thought you set. If you notice, in that picture of my panel, not only is the 930 on the pilot's side, we moved the AP annunciator over there as well so it is within your scan to see that the AP is engaged and the right mode is engaged. Also the GPSS (the strip just right of the AP annunciator), so the pilot can check what mode the GPSS is in. The only thing I can think of that would be nice to have on the pilot's side, that is still stuck over on the co-pilot's panel, is the vacuum. 

One advantage of digital technology in general is that more things are consolidated in smaller packages, so the more digital the panel, the less the co-pilot's side is needed for anything except maybe secondary instruments like a second or third AI/HSI.

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  • 2 weeks later...
On 2/12/2021 at 5:56 AM, Sheriff23 said:

Good to know.....upgrading to a 900 is on my wish list.

Sheriff23, check with Costaero about what kind of deal they can get you on the 900. Seems like everyone is pretty competitive with prices right now, within $100 dollars of each, but every time I've called Chris or messaged him, I've gotten a response within a few minutes.

I was undecided on what to get in my C next, (355, 430, 830, AV-30C, 327...) but figured engine monitor will pay off first, both in safety and possibly fuel saved (I'm really hoping my carburetor induction system is tuned like a dragster! even flows!) Also I figured I might make $1000 back from old gauges possibly.

Anyways, good luck. Was told build time will be about 8 weeks once order is placed.

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