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Fuel injection or carbureted.

Dbro172

Well Known Member
What was your reasoning for selecting one over the other; fuel injection or carbureted? (Cost, simplicity, complexity, efficiency, tank mods, other mods, etc.)

Just gathering some opinions and thoughts to help in my selection, your input is appreciated. Thanks,
 
I went with new carbureted O320 because of cost and simplicity. In 2008 dollars I paid 19K and a change for brand new YO320-D2G.
 
I'm definatly going fuel injected. Isn't too much more money, can be operated LOP generally and the biggest reason is sustained inverted flight.
 
We have two carburated O-360's, and our newest plane has an IO-320...just to be different! The carbs are simple, easy to operate, very predictable to start. The Injected engine runs very smooth, we can get it far leaner than the carbed ones for long, high cruise, but we're still learning to start it in "odd" situations - hot, high density altitudes, etc.

I know how to fix the carbs if I have to - the FI system will probably need to go to depot maintenance if it has a problem - but it has been perfect so far!

Paul
 
...The Injected engine runs very smooth, we can get it far leaner than the carbed ones for long, high cruise, but we're still learning to start it in "odd" situations - hot, high density altitudes, etc...

Having observed the little tantrums of that particular airplane a few times I would be interested in hearing more detail. What have been the most difficult situations (I think I know) and is a method near perfected that makes for a reliable start?
 
Having observed the little tantrums of that particular airplane a few times I would be interested in hearing more detail. What have been the most difficult situations (I think I know) and is a method near perfected that makes for a reliable start?

Well, we haven't had Tsam out at high density altitudes since that first trip, but we've come to peace with hot starts here at sea level through "standard" hot start techniques - if it is a "quick turn", no prime, and bring the mixture in slowly when it fires. We have been more careful to leave the oil door open during turn-arounds, but I am not sure it makes that much difference - this is a pretty cool running engine overall.

I think the key to my own learning curve has been to bring the mixture in smoothly when it fires - sometimes, you don't want to go full rich, and often, "teasing" it in makes for a smoother start.
 
Fi

The Injected engine runs very smooth, we can get it far leaner than the carbed ones for long, high cruise, but we're still learning to start it in "odd" situations - hot, high density altitudes, etc.
Paul

I ended up with Fuel Injection, not by choice but by chance. Am I ever glad I did!

Yes, hot starts are a problem for some people but an old grizzled pilot (at least older than me!) told me to treat hot starts like flooded starts much in the mannor that Paul mentions. That has worked every time for me with my engine in the 500+hrs. I've flown it.

With Robert Paisley's EFII dual electronic ignition, I can go lean of peak on the EGT and get the fuel flow down to 7 gph at 8000ft at 2300rpm and full throttle. That setting gets me about 166-167 knots TAS. Not to shabby for a 200hp IO-360.

ps: It sure ticks off my buddy with a 180 hp RV-8 when we fuel up and I put in 2 to 2 1/2 gal less after a two hour flight!:D
 
I went with the IO-320 as I was concerned about rising fuel prices and I figured, with LOP operation, it would be less expensive to operate. While probably true, it may take a few hundred hours of operation to recoup the added expense.

I have not had significant issues with hot starting. I can shut down to fuel up and, even in sunny Florida over the summer, I have always been able to get it going again.

If I were to do it all again, I would probably go with a carb for the simplicity. For the FI, other than removing and cleaning the injector lines and cleaning the filter in the throttle body, I won't touch it; whereas I would have no problems tearing into a carb. But, I have no regrets with the FI system and, unless it starts needing some expensive repairs, I am sure I never will.
 
Investment Opportunity

I went with new carbureted O320 because of cost and simplicity. In 2008 dollars I paid 19K and a change for brand new YO320-D2G.

Today, that engine is $25,700, which is $2000 more than when I started building 7 months ago. Which is a 35% increase over what Vlad paid for it 2008. (WTF)

So, if I assume a 10% increase per year... If I buy 10 engines today, sell them in four years for 20% more than I pay for them, I will make $50k profit and 10 people will get a steal (20% discount) on their engine.... Hmmmmm?

That ain't going to happen, but I hope I can still afford it when I need it.
 
I grew up with an injected engine in my dads Mooney, and flew Arrows for most of my rental days.
Same with CS prop.

I know all the arguments pro and con but the real reason I purchased is I just plainly like both injection and CS. Personal preference.

If it were not for that, and budget ruled, carb and FP would certainly be the way to go.

Edit ***
old grizzled pilot told me to treat hot starts like flooded starts
AMEN!! ;)
 
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My 172 is the first injected plane I've had, and I absolutely fell in love with that system after dealing with carbs before. I'm a big proponent of lean-of-peak in cruise (I'm an engineer, efficiency just appeals to me:D) and matched injectors by GAMI make that very easy to do. There was never really any question of what I would do on my 9A, I knew it was going to have an injected engine before I ordered the empennage kit.
 
Injection

Lycomings are generally not known for carb ice on the carburated engines.
However two fatal accidents, one EAB, one standard category, both four cylinder Lycomings, have caused me to reconsider the subject. Ironically both of these accidents were traffic pattern accidents and loss of power was followed by loss of control.
It sure is nice with the fuel injection not to have to worry about carb ice, especially when there are other distractions.
 
I went with injection because a) I did not want the constant nuisance of carb heat, b) I want to run LOP most of the time for peak efficiency, c) I have flown injected 172s for 6 years and like almost everything about injected Lycos vs carbed Lycos. The "almost" is the hot start issue ...that can admittedly be a pain.
 
Injected because 1) no carb heat or icing issues; 2) ability to run LOP. Cost differential in 2008 was about $300, so very worthwhile on that front. I've only had about two times early on when I had difficulty starting hot.

Greg
 
When spending cubic dollars on you plane you have to ask, will a few more really matter?

In my opinion, nickel and diming is never the answer to anything. Some things justify doing it the cheapest, but very few in aviation.

Go the IO ;)
 
Resurrecting this necro-thread to see if there are new opinions.

What was your thinking re:carbureted vs injected? Would you do the same thing again?

As a big fan of simplicity, I'm leaning toward carb/FP, but lots of people probably think I'm wrong on both counts.
 
I started with a carb (Included with a core that I bought) on my 320 and upgraded to FI. The FI setup was purchased here at a reasonable price as it was used. The balanced injectors allow me to run more than .5 GPH lower at cruise power (~ 30* LOP) with no speed loss. The carb distribution was very poor and two cylinder were running WAY richer than the other two. With 500 hours on my plane, I am getting close to breaking even on that purchase.

Larry
 
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Fuel injection:

No need for carb heat cause no chance of carb ice,
Simpler to operate if you consider the effort to get it set up to cruise LOP. Some carbs will never run smooth LOP so you save all that fiddling time,
Hot starts have not been a problem for me
Possibly a little heavier install for FI
Would definitely do FI again.

Bevan
 
Carb for the simple reason that I want to operate far from paved runways. If I ever leave the master on, I want an airplane that I can easily hand-prop to get me out of the woods.

(I know, don't fly with a depleted battery... Thanks, I'll fly with a depleted battery rather than taking my chances on being driven insane by blackflies and mosquitos or mauled by a grizzly. If you've spent time in some of the places I've spent time, you'll also understand this reasoning. If you haven't, thanks, this reasoning isn't up for negotiation.)

On the other hand, it looks like our engine may have very poor fuel distribution so I may be forced to go to Injection just to get the range I need to get to the places I want to go. Catch-22!
 
FI Pros:

* Will eventually pay for itself via fuel savings.
* Should run smoother once injectors are tuned since each cylinder will be making about the same amount of power via more precise fuel/air mixture.
* LOP cruise operation may result in fewer fouled plugs, stuck valves and other lead related issues.

CON:
* More expensive up front cost.
* More installation time.
 
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