GAMIjectors worth it?

[Badmoonraising]

Have a 64 M20E and I am considering the purchase of GAMI injectors. Any and all advice appreciated. I should mention that my EGT/CHT is only on one cylinder. However it seems to me that replacing really early type injectors has to be the right move. Even if I can't see every cylinder temp. Shirley the spread should be less. 

Am I thinking straight on this?

[Bunti]

Gami Injectors make most sense, if you have engine fuel flow and EGT-data from every cylinder. The company is great. They will send you finetuned injectors for every cylinder to make them peak at the same time, when you lean.  The difference between the first and the last peak is called the "Gami-spread". But without an engine monitor, you are not able to find out about the Gami-spread and you will be unable telling Gami which injectors you need.

For my Mooney, I first bought an engine monitor. After that, I recorded the different peak values of the cylinders and sent the data to Gami. With this information they were able to produce the right set of injectors for my engine. If - after installing the new injecors - the cylinders are not peaking at almost the same fuel flow, they will exchange one or more injectors until everything works perfect.

I suggest, that you start with installing an engine monitor. I consider the engine monitor as one of the most important pieces of equipment in my Mooney. It tells me what is going on in my engine. There are lots of possible engine problems which you will not see without an engine monitor. For example, I had an intake leak on one cylinder. The monitor showed an alarm and I reduced power, landed and got it fixed immediately. Without the monitor, I would not have seen it and I may have destroyed the cylinder.

 

[Guest]

Save the money and buy an engine monitor first.

Clarence

[RobertGary1]

I don’t think think gammi will even sell you injectors if you have a single egt. They wouldn’t be able to tune them for you which is the entire benefit of gammi

 

-Robert

[gsxrpilot]

Without a proper data logging 4-EGT/4-CHT engine monitor...

• You can't know if you need GAMI's
• You couldn't know how to order them, tune them, or know if they made any difference
• You can't run LOP, which is the whole purpose of the GAMI injectors
• You don't have any idea what your engine is doing anyway, so why do you care

Best budget engine monitor - GEM G2
Replace all stock/failing gauges - JPI EDM-900
Money and panel space is no object - EI MVP-50

[Oldguy]

5 hours ago, Badmoonraising said:

Have a 64 M20E and I am considering the purchase of GAMI injectors. Any and all advice appreciated. I should mention that my EGT/CHT is only on one cylinder. However it seems to me that replacing really early type injectors has to be the right move. Even if I can't see every cylinder temp. Shirley the spread should be less. 

Am I thinking straight on this?

1. Get an engine monitor installed. @gsxrpilot has a good selection listed.
2. Fly the plane, recording all of the flights for a while - not just one or two flights - but enough to see how your engine is performing in various situations.
3. Go to www.savvyanalysis.com and print off their Flight Test Profile document and do what it outlines.
4. Upload all of your data to www.savvyanalysis.com and run their GAMI spread analysis on several of the flights. If you want, you can pay a fee to have their specialists analyze your Flight Test Profile flight to give you several items, more than likely, to address with your mechanic. @kortopates can expand on this.
5. Talk with your mechanic and decide what you want to do to improve your engine's performance based on the reports from Savvy and your review of the data.
6. Continue capturing and uploading to Savvy to monitor performance and tune appropriately.

Some (most?) of the Lycoming IO-360 engines do pretty well on their GAMI spread with everything else being nominal on them. My J has a GAMI spread in the 0.2 to 0.4 GPH range, but others have had enough variation on their engines the GAMIjectors have made a big difference.

As with all things related to our engines, YMMV.

[kortopates]

The fact is that most lyc io-360 engines do not need gami's. But every engine needs a good engine analyzer! Learning how to use one could give you plenty of warning to avoid a catastrophic engine falure as well as pay for itself in diagnosing engine anomalies.


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[Badmoonraising]

Thanks for the advice. That's really good and detailed information. Unfortunately it doesn't really answer my question, or perhaps it does but I'm not hearing it. 

Let me restate my question; Is it not logical to put the GAMI injectors in as they have higher manufactured tolerances? They have to be better than the early injectors manufactured back in 1964! In fact I might argue that considering that currently I am only monitoring one cylinder is not even more important? At the very least it should narrow the gap between the cylinders?

I agree with Oldguy's post. I would ideally go the whole route but in the meantime - at least put in injectors that are known to be tuned. 

Again, am I thinking about this correctly? Or am I throwing money at something blindly?

Very much appreciate the replies....

[LANCECASPER]

7 minutes ago, Badmoonraising said:

Again, am I thinking about this correctly? Or am I throwing money at something blindly?

No, Yes

[carusoam]

Badmoon,

There is a test to tell how well your injectors are delivering fuel...

It is called the Gami spread.

Need an engine monitor to run the test.

a minimum amount of knowledge is required.  Not too much.

Visit the Savvy website for a page or two of reading.

visit the Gami website for another page or two..

Add dynamic prop balancing....

you will have the smoothest engine running...

Need some links?

If not familiar with the Gami spread... you would not be thinking about this correctly... spending additional money on fuel injectors without an engine monitor would define throwing money blindly...

Want some help?  We are pretty good at spending OPM...

Best regards,

-a-

[Badmoonraising]

Thanks thats great. The recurrent suggestion is to get an engine monitor. I've read through the GAMI website. As one of the principles Engineers there stated. I really have four single cylinder engines at this point. I monitor just one of those engines. So yes it is a given that all four need a monitor. But in the short term is it not logical to have better tuned injectors? At this point I'm flying blind as far as fuel flow goes to each cylinder so better tolerances with injectors becomes even MORE critical with only one cylinder monitored. 

[carusoam]

Resist all you want, badmoon...

in your words, again...

1) you have four individual engine processes...

2) you want them to deliver a balanced (the same) output...

 

To do that... it requires the best available...

3) balanced air input... (a four cylinder engine has pretty good air balance)

4) balanced fuel input... (fuel balanced injectors can help, but not necessarily...)

5) balanced spark delivery... and spark timing... (seen any Champion spark plug issues around?)

6) balanced cooling, will be next on the list...

 

To know you have all this balance...

7) An engine monitor is the number one technology to have.

Without an engine monitor, something will change....

When something changes will you know it?

Will you know what to do with it?

Will you need to change your destination, quickly?

Can you tell your mechanic what you need?  Share your JPI graphs around here or with Savvy you can get proper help.

Fun things to read up on that can be identified on the fly using an engine monitor...

• blocked and semi-blocked fuel injectors...
• misbehaving spark plugs.
• stuck valves.
• Fuel flow.
• LOP with precision.

Best regards,

-a-

 

[N201MKTurbo]

My experence is the Lycoming injectors are made extremely well. It is hard to imagine that GAMI makes better injectors. What they do is make them custom to fix problems with some engines. The engine in the early 231s had horrible mixture distribution because of a poor intake plenum. The Lycoming intake is excellent.

[carusoam]

For six cylinder engines... have a look at the curvy pipes that are needed to get balanced airflow to all cylinders...  

Go TPFI! So much better than the MPFI.  (‘80s auto references...)

Somebody posted a nice picture yesterday...

Best regards,

-a-

 

[tangogawd]

Lycoming typically have good fuel distribution. You will likely not gain any improvement with out the box gami's. You can gain improvement by doing their gami test and swapping out injectors. You will need an analyzer to do it. My engine with factory injectors is around .5 gph, I would gain very little if anything. 

 

[N201MKTurbo]

Also make sure you thoroughly clean your current injectors before doing your GAMI test. I’d hate to see you spend all that money to fix dirty injectors.

[kortopates]

2 hours ago, Badmoonraising said:

.... At this point I'm flying blind as far as fuel flow goes to each cylinder so better tolerances with injectors becomes even MORE critical with only one cylinder monitored. 

Not at all. Don't confuse between injectors being tuned to each other with similar flow to suggesting this will result in better tuned cylinders that peak at the same fuel flow because it does NOT mean that. The point of the injectors is to provide different flow rates to different cylinders that otherwise run leaner or richer to one another so that with the different flow rates they peak closer together.

But your current limitation is monitoring of one cyl only. Which limits you to running ROP. But say for example you want to avoid the harmful red box by running 100 ROP - is it safe to just to find 100 ROP on the one cyl? No - not really, you want all 4 to be 100 ROP, so you add more mixture for good measure but really never know when all 4 are 100 ROP. Adding gami's won't change that. But the engine monitor will allow you to set mixture accurately to keep all 4 of those cyl's to your target amount ROP (or LOP) without having to run extra rich just as insurance to keep other cylinders out of the red box. (it wouldn't even work on to go extra lean on the LOP side because running  LOP requires setting mixture very accurately unlike ROP) 
Get the engine monitor - that's what will provide you with real leaning effeciency right now.
80-90% of the lyc io-360's do NOT benefit from gami's - you most likely will not need them.



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Edited July 10, 2018 by kortopates

[carusoam]

Nice example of a good Gami spread, Tango.

.1 or .2 would be really good.

1.0 would be a sign there is a lot of room for improvement...

A financial savings point of view for this...

If you are running at peak @ 10k’ and one of your cylinders peaks 1gph later than the others....

• one cylinder is really delivering less power than the last to peak...
• if you lean only til the first one peaks... that leaves an extra gallon of fuel per hour being tossed overboard... @ $5 per gallon... or $5 per hour... a whopping $500 per year that can be better utilized. (@10 hour’s per year)
• this is a pretty rough financial example based on a pretty lousy Gami spread.

Best regards,

-a-

[Badmoonraising]

Okay, that it. I need an engine monitor, all four...

Thanks for the input. Extremely valued. 

[carusoam]

What else ya got Badmoon?  

You have heard from some pretty smart people... some mechanics... some instrument guys... some engineers... all Mooney pilots...

Some are really good at delivering the message.

Then there is me...

Summary...

1) Get engine monitor

2) Run Gami Test...

3) report what you find...

4) A crummy spread may indicate fuel injector cleaning is in your future...

5) A good Gami spread may indicate lots of LOP (money saving) can be in your future...

6) Having a monitor gives you more to feel confident about..

7) An engine run-up with data is better than no data...

8) Before rotation, MP, RPM, and FF are nice to have before committing to flight...

9) Additional alarms can be good to have...

There are so many pieces of technology to select from...  need some advice?  Got a

 tight budget? There are some really good used ones coming available often...

Best regards,

-a-

[carusoam]

To answer the original question...

Gami injectors are worth it, when...

1) The Gami spread indicates that fuel is being wasted hourly...

2) Cost of wasted fuel, annually = The price of fuel X gph being wasted X hours per year...

3) Compare the price of Gamis, and installation cost to the cost of wasted fuel...

4) If the cost of fuel wasted, and the cost of gamis, is pretty close, it makes a lot of sense...

5) If you clean your fuel injectors, and test with the baby bottle test... and they are really close... special injectors may not help an extrem amount...

6) balancing the fuel system before cleaning the air intakes and fuel injectors would kind of like being putting the cart in front of the horse...  

7) then balance the prop... for the ultimate smoothness..... for a four cylinder...

Best regards,

-a-

[Badmoonraising]

The obvious question now is; which monitor system? 

[HRM]

9 hours ago, M20Doc said:

Save the money and buy an engine monitor first.

Clarence is dead on here. My 50+ year old E has a GAMI spread of 0.1. How do I know? I upload data after every flight from my EI MVP-50 to Mike Busch's Savvyanalysis site (free). His software will calculate GAMI spread for you. IIRC, he told me that most IO-360's don't need GAMI's. 

Disclaimer: he let's you upload, store and analyze your flight data for free because he uses it in his own engine research. Win-win as far as I am concerned, but if you are a conspiracy theory or privacy nut you may not want to participate .

[carusoam]

Is It going in a forever plane?

are you on a tight budget?

Do you like the big brand name?

Do you prefer the best customer service?

Are you going all electronic instrument panel in the future?

Got room in your panel?

want to replace some of the old analog gauges?

I love instrument shopping.

Want to add the best FF and FL to that?

Best regards,

-a-

[carusoam]

Forever planes often get complete data monitoring and data storage of a vast array of data...

Some advantages include constant monitoring of fuel flow, FL, and distance to destination... with an alarm if something doesn’t look good.

Three most popular brands...

JPI

EI

Insight

Forever planes often get monitors that can replace the ship’s original analog instruments..

Lots of instrument panel space... gets large monitors with easy to read data all on one screen...

tight on space, low dough available, Insight makes a nice instrument, but may require two do do everything, or flipping pages to get most of everything...

EI and JPI make some of the finest, but more expensive solutions...

Garmin has an engine monitor integrated into its latest color touchscreen panel mounted navigator...

Best regards,

-a-