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Ok, Lycoming! But carburated of Fuel Injection

MaguireFlyer

I'm New Here
Well, I'm no where near the FWF yet (just started) but I've read all the "noise" on alternative engines vs the tried and true. I am planning to go
with the tried and true but wondered what the pro's and con's are to going fuel injected rather than the standard carburated.

Any thoughts on this matter (I'm not trying to start a long debate here :) )

Stay Safe
David
 
FI will "pay for itself"

Fuel injection will be thousands more expensive. But... If you go with fuel injection and operate it effectively, the system will "pay for itself" within about 1000 hours. At least that's what I calculate according to today's crazy gas prices.

There is higher acquisition cost up front for the FI $y$tem and its supporting component$ (i.e. high pre$$ure boo$t pump), but I believe it's well worth it. That's just my perspective.

So given that it's more or less a wash cost-wise, it just comes down to whether or not you want fuel injection! What do you want?

What's the down side? Hard to hot start sometimes? I guess. If that's the worst of it, it ain't bad.

What's the up side? Precise fuel metering to each cylinder -- which by itself isn't all that enthralling of an advantage. But it does allow you to run LOP. Couple that with an electronic ignition, and you've got the ability to run extremely economically. And you'll never have to deal with problems where "swap out the carb and see if it goes away" is the best answer. I follow the Lycoming list, and I'm amazed at how often that is actually the best course of action!

FWIW, my 200hp IO-360-A1B6 RV-7 burns less fuel when side-by-side at any speed with all other RVs I've flown with. This includes lots of 180hp O-360 RV-6s, and 160hp O-320 powered RV-6s, even when I'm "throttle jockeying" in formation and the O-320 RV-6 is in the lead with a steady-state best economy power setting. Somehow I manage to take on less fuel at the pumps. Slightly less -- it's not a huge difference. But I personally believe fuel injection + electronic ignition is the ticket (albeit with an up-front price) to better economy.

If economy and "precision" aren't the long term goals, then maybe it's not worth it. The difference is definitely not huge by any stretch. It's almost picking nits. Just depends on what you want out of your powerplant.

)_( Dan
RV-7 N714D
http://www.rvproject.com
 
Checkoway: best builder's web site hands down. Superb.

David: "payback" is highly dependent on leaning skills of individual pilot. best bet is to consider it a wash and focus on other pro/con items to reach decision.

FI
GOOD inverted, no ice, LOP, clean cowl
BAD cost, vapor lock, electric
UGLY fuel pump

CARB
GOOD cheap, simple, low pressure fuel, non-electric
BAD icing, no LOP, higher CHT spread
UGLY ugly

EI
GOOD better combustion, smoother running
BAD cost (minimal w/mag credit)
UGLY electric dependent, fragile

there really is no "best" answer. if you plan to fly IMC, it's a toss up between carb (icing) and electric failure (FI) but FI is probably the better edge. For VFR it's strictly personal preference. EI is money well spent. For me, the best overall combo is O-360 w/EI on 1 side.
 
I've never had an FI plane, but I can tell you I have never had any problems with two trusty 0-360's and one 0-320 carbureted engines. They're simple, cheaper to buy, easy to maintain, have been reliable, and I think they are beautiful.

Personally, when I saw the Van's 7A with the FI cowl, I was disappointed 'cause I thought they did away with the neat scoop.

Roberta
 
From a purely engine perspective, the FI is way more efficient and would be the way I would go if I could afford it. If money was tight then the carb is second best choice to me. You can always change to FI down the road, relatively easily, if you find you made a mistake going with a carb. When the FI is mounted vertically you still use the air scoop, it's only when it is mounted horizontally that the snorkel on the lower cowl goes away. I like the way the aircraft looks with the snorkel too.
Good Luck,
Mahlon
"The opinions and information provided in this and all of my posts are hopefully helpful to you. Please use the information provided responsibly and at you own risk."
 
My first plane was FI. No problem starting it, once I learned how.

But, I went carburetor on this pane. It is also lighter by a few pounds, but mainly I wanted the super easy starting, and simplicity....


One other point, the periodic rebuild of the Bendix/silverhawk style systems is more than $1500 each time. I have heard that the airflow performance systems are somewhat cheaper.

In the end it is probably a preference thing, although with FI, and EI and a good pilot (remember DCheckway is skilled with lots of complex hours) is more fuel efficient.

My plan as to build a cost effective cruiser that good go as fast, or a little faster than the 201 I rent, on less fuel. I believe I will be able to get 160KTS at 8 GPH out of my O-320 rv-7, by keeping it clean and going with the James cowl. If so, it will be a great little cruiser for us.
 
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Thanks All

Those answered helped out a lot. Now I have a much better idea of where to let my mind wonder over the next couple of years building. I'll probably just go with the Carb until I have actually accumulated some hours on the equipment.

Great website Dan!

David
RV-9A
 
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