Might be a bit more than that depending on what you have now concerning your electrical system.
Electronic fuel injection needs a constantly running electric fuel pump and that one consumes quite some power, meaning you are going to need a second source for that kind of power.
I am putting in two EarthX batteries and two alternators to have full redundancy.
I have an O-540 A4D5 on my -10. I am considering the idea of upgrading to fuel injection. Is the efficiency worth the expense (~$5k) or should I keep it simple?
Maybe you meant to say "save 2 to 3%??" over a carbed engine?With injection, running lean of peak in cruise you save 20-30% of fuel for only a 5% reduction in speed
Maybe you meant to say "save 2 to 3%??" over a carbed engine?
That would be somewhat accurate and more realistic and perhaps a 5kt speed reduction if you are able to run on the extreme side of LOP or about 10.5 gph. Snip
Maybe you meant to say "save 2 to 3%??" over a carbed engine?
That would be somewhat accurate and more realistic and perhaps a 5kt speed reduction if you are able to run on the extreme side of LOP or about 10.5 gph.
I certainly would not trade my IO-540 for an O-540 but fuel savings would not be motivating enough for me to consider an upgrade, especially if I already owned a perfectly well running carbureted version.
You'll be down for a considerable amount of time to upgrade all the necessary IO components, like high pressure mechanical fuel pump, high pressure boost pump, etc.
If you go down the rabbit hole of adding a new electronic ignition, pmag or other, you'll spend closer to $10,000.
If you saved a gallon per hour <8%> highly unlikely, it would take you over 1400 hrs to break even.
I have an O-540 A4D5 on my -10. I am considering the idea of upgrading to fuel injection. Is the efficiency worth the expense (~$5k) or should I keep it simple?
The efficiency gains of moving to FI are only partially realized unless you have a means to optimize your ignition curve for LOP ops. Mechanical FI gets you a little; adding an EI with a cookie cutter curve gets you a little more; but installing a fully adjustable EI from SDS along with an optimized curve and tuned nozzles gets you about as good as you can get with a SI engine.
The "Full Monty" of course is the SDS EFI.
If you are looking for a way to dip your toe in the water, the best bang for the buck you can do right now is buy a single CPI ignition. You can do one side for about a grand and will lay the foundation for the future. The old saw about "the first EI gets you 70% of the benefit of dual EI" is true - but only if you are discussing the typical EI with a pre programmed curve. Choosing SDS allows you to optimize that one EI to "almost" eliminate the need for the second (from an engine efficiency standpoint).
Spend a few bucks and buy the CPI, tune it for the best LOP ops the carb delivers and see what happens. If you are still trying to eke out some more efficiency, look to FI as the next step.
That is my experience as well.In my 10 at 8-10K I get a very reliable 165 KTAS at 10.5 GPH.
That is my experience as well.
But to validate a 20 to 30% reduction over a carbed version, I want to know what your experience shows for comparison or do you just assume a number to make the savings look real good?
Maybe the OP could post some numbers based on his O-540 installation?
We could split the assumption and take 25% fuel savings.
That would mean that a carbed version burns 14gph x .25% reduction=3.5gallons. Now you are at 10.5 gph.
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I have an O-540 A4D5 on my -10. I am considering the idea of upgrading to fuel injection. Is the efficiency worth the expense (~$5k) or should I keep it simple?
The 20-30% fuel savings has no assumptions. It is comparing running LOP vs ROP with the same injected RV-10.
This gives the OP a data set to contemplate: Fly LOP at 5-8 knots slower burning 2.5-3 GPH less (out of 13 GPH) vs keep blowing gas out the exhaust with the carbed engine and fly a little faster.
Induction System – Lycoming O-540 series engines are equipped with a Marvel-Schebler MA-4-5 carburetor. Particularly good distribution of the fuel-air mixture to each cylinder is obtained through the center zone induction system, which is integral with the oil sump and is submerged in oil, insuring a more uniform vaporization of fuel and aiding in cooling the oil in the sump. From the riser the fuel-air mixture is distributed to each cylinder by individual intake pipes.
I tried to reply to share my numbers…just landed from an 1100 NM trip.
Economy cruise at 15,000’ 14”/2300 9 gph at 155 TAS
Normal cruise at 14,500 19”/2400 163 TAS 10.3 gph
Lower altitude leg, 10,500’ 21”/2300 162 TAS 10.5 gph
If I crack the carb heat, I can get all EGT’s within 25 degrees and run 75 degrees LOP.
Mark, are these numbers knots? If so, your carb is doing very well.
There are many advantages to an injected engine especially in conjunction with electronic ignition systems but claiming 20 to 30% reduction in fuel consumption is simply not true.
Yes speeds are in knots. I took a friend who has FI yesterday and he agreed that about the only gain would be smoother LOP running. I have one SureFly SIM that helped a lot but it is not smooth at the LOP i listed. I usually run close to peak and give up 1/2-1 gph.