Today's Message Index:
----------------------
1. 12:08 AM - Re: Fuel Return Line Location? (Justin Jones)
2. 07:41 AM - Re: Fuel Return Line Location? (Kelly McMullen)
3. 09:04 AM - Re: Fuel Return Line Location? (Justin Jones)
4. 07:15 PM - Re: Fuel Return Line Location? (Rocketman1988)
Message 1
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| Subject: | Re: Fuel Return Line Location? |
The wide band O2 sensors will eventually burn out due to lead fowling. They are
pricey, and it does not happen in less than one tank of 100LL. There are many
guys that have used them for tuning and removed them when they are done with
them. Not a good idea to keep them in as they will eventually burn out completely.
If you plan on changing your fuel map, I would HIGHLY suggest using a wide
band sensor and a display to ensure your AFR (air fuel ratio) is not getting
to lean. The stoichiometric ratio for a natural aspirated engine is 14.7:1
It is safer in our aircraft engines to run them at 13.7:1 and thats what the
EFII systems stock fuel map is programed to provide. Another indicator of the
AFR is EGT, but other things can affect EGT, so the safe bet while tuning is
to use a wide band O2 sensor and an AFR gauge to display the correct number to
ensure you dont get too lean.
The EFII system for me, was a cost benefit to overhauling what I currently had.
An RSA5 fuel injection overhaul, new fuel pump, new mags, wires, plugs etc would
have been at or above the cost of acquisition of the EFiI system. I have
heard nothing but good from this system and Robert Paisley from ProTec Performance
has been nothing short of a rockstar with his customer service. I would
agree that more benefit comes from the EI than the fuel injection, but by modulating
the injectors, they are seeing gains on the dyno with the Electronic Fuel
Injection over the mechanical injection. Also of note, the Lycoming hot start
issue disappears with the EFII fuel injection. Mixture management is simple
with the EFII system due to the programed fuel map they have in the ECUs.
It reads the Manifold pressure, RPM, Throttle position sensor, and comes up with
the fuel demand for the engine regardless of altitude. There is NO MAF sensor
in this system. It uses a similar sensor in the throttle body. If you wish
to trim fuel to change the EGTs, you can do so with the mixture rheostat, or
you can do it by reprograming the ECUs fuel mapping. Takes some programing
knowledge and the software, but its not hard to do. Robert Paisley and or SDS
can help with this as well. There is significant fuel savings with this system,
but as Kelly stated, it is not half the fuel.
Robert has his EFII system on numerous aircraft that race in the Reno air races,
as well as many many happy customers flying the complete system. The ECUs are
SDS ECUs and have hundreds of thousands of hours tested on them. The fuel pumps
are automotive type, and there are 2 of them. Tons of proving time on the
fuel pumps as well. The Coils are similar (if not the same) as the one from
a Subaru Impreza. Again, hundreds of thousands of hours on the coils as well.
The spark plugs are iridium automotive plugs and are a fraction of the price
as an aircraft plug and out perform them as well. I feel perfectly safe with
the EFII system in my aircraft, and would recommend them to anyone who wants a
traditional aircraft engine with a modern fuel and ignition system.
Hope this helps!
Justin
On Apr 20, 2015, at 11:43 AM, Kelly McMullen <kellym@aviating.com> wrote:
>
>
> I assume you are aware that leaded fuel such as 100LL will destroy an oxygen
sensor in less than one tank of fuel?
> I seriously doubt that the EFII system and the dual everything required to ensure
it has power to work will save enough fuel to have a payback in any reasonable
time frame. Mixture management on conventional fuel injection with magnetos
is childs play once you get the system delivering equal fuel mixture to each
cylinder. While autos are using less gas and producing more power, they are
doing it with higher compression ratios, knock sensors and thousands of hours
of dyno time. Most of the incremental benefit comes from electronic ignition,
not electronic timed fuel injection. Feel free to experiment, but don't expect
to get equal power on half the gas, or half the workload, for equal investment.
>
> On 4/20/2015 9:55 AM, Berck E. Nash wrote:
>> Since the fuel is metered directly at the injectors by the ECU, why do you have
to mess with the mixture knob? The EFII website says, "Automatic mixture
control (no mixture knob to fool with)", but you're saying that's not entirely
true? Is the issue that you're compensating for a lack of initial ECU programming
by altering the fuel pressure until the you get the programming dialed in?
Since the system has a MAP and IAT sensor, it seems like it should be able
to meter correctly without any input from the pilot. It doesn't look like the
EFII includes an oxygen sensor, though?
>>
>> Any idea if there are plans to fly this plane on automotive gasoline?
>>
>>
>>
>>
>> On Mon, Apr 20, 2015 at 10:38 AM, Jesse Saint <jesse@saintaviation.com <mailto:jesse@saintaviation.com>> wrote:
>>
>> I think you're kidding yourself if you think there is no mixture
>> to worry about. I spend more time on the mixture knob so far than
>> I do on the mixture control with a standard system. It's possible
>> that once you get things all tuned up the way you want them you
>> may not use it as much, but I really don't use it that much on a
>> standard system either. I lean a little as I climb, then I set
>> power, rpm and fuel flow for cruise.
>>
>> I would imagine if you are burnin 12gph, you are probably
>> returning at least that much to the tank, if not more. I wouldn't
>> want to have to mess with picking a return tank separate from a
>> feed tank. There are warnings when your fuel in a tank gets low,
>> but I don't know of a warning saying your tank is getting too
>> full. If you get busy or get bored and aren't managing fuel with a
>> normal system, you will get something yelling at you saying you're
>> getting into the red on the draw tank, but it won't happen if you
>> start to pump it overboard through the return tank vent.
>>
>> I agree that electric ignition is tried and true in cars, but so
>> far there are a total of 10 fleet hours in the RV-10 with a full
>> EFII system and thousands and thousands with mags and standard
>> fuel injection. Far from a no-brainier in my book unless you are
>> talking the other way around.
>>
>> Jesse Saint
>> Saint Aviation, Inc.
>> 352-427-0285 <tel:352-427-0285>
>> jesse@saintaviation.com <mailto:jesse@saintaviation.com>
>>
>> Sent from my iPad
>>
>> On Apr 20, 2015, at 11:58 AM, Berck E. Nash <flyboy@gmail.com
>> <mailto:flyboy@gmail.com>> wrote:
>>
>>> Carl- thanks so much for the picture. I'll plan on the same
>>> location. As for the cost: We haven't purchased anything yet,
>>> and probably won't until we source an engine. Hoping available
>>> systems will only get cheaper, but cursory research indicates
>>> it'll cost not much more than more conventional FI and ignition
>>> setups.
>>>
>>> Jesse- Thanks for the heads up. Glad to hear that one is flying
>>> already, and I hope you'll keep us updated of any gotchas. After
>>> seeing that an EFII system is available, I can't imagine not
>>> using it. I'm aware of the need for a fully redundant electrical
>>> system and dual ECU's. I was already planning on dual electronic
>>> ignition and the dual alternators that necessitates, so
>>> electronic fuel injection only makes sense to me. This is, I
>>> think, the beauty of building an experimental-- the ability to
>>> use "modern" (30-year-old tried-and-tested) technology in an
>>> airplane, instead of being forced to rely on a fuel delivery
>>> system from the 1950's.
>>>
>>> Any RV-10 specific EFII links, information, vendor tips, etc,
>>> would be greatly appreciated.
>>>
>>> As for the "complexity" of a fuel return tank selection, it seems
>>> a bit silly to me that choosing a return tank is considered
>>> "overly complex." It's the difference of switching two valves
>>> instead of one when you switch tanks in normal operations. Sure,
>>> it's more complex than a single knob, but I'm used to much more
>>> complicated fuel systems many of which require deliberate
>>> knowledge of the fuel return tank. I'm not really concerned
>>> about it either way. The only reason to want to transfer fuel
>>> would be a leak, and in most situations, getting on the ground
>>> quickly makes a lot more sense than moving fuel around. Since I
>>> won't have to worry about the insane complexity of a mixture
>>> control, I can use those saved neurons to handle the fuel return
>>> tank if I wind up with two valves.
>>>
>>> On Mon, Apr 20, 2015 at 7:49 AM, Carl Froehlich
>>> <carl.froehlich@verizon.net <mailto:carl.froehlich@verizon.net>>
>>> wrote:
>>>
>>> Berck,
>>>
>>> I added a 1/4" purge line return to the left tank when
>>> building in case I
>>> ended up with an AFP injection system (photo attached). This
>>> is the same
>>> location I used the RV-8A which had AFP injection.
>>>
>>> Adding a return line is straight forward and if you get the
>>> fitting in about
>>> the same area as the vent line connection you should not have
>>> an issue. I'd
>>> keep it high (like my photo) so that it is away from the fuel
>>> pick up -
>>> should help with pulling cooler fuel into the engine as
>>> compared to the
>>> hotter return fuel.
>>>
>>> Just curious - how much did this EFII system cost?
>>>
>>> Carl
>>>
>>> -----Original Message-----
>>> From: owner-rv10-list-server@matronics.com
>>> <mailto:owner-rv10-list-server@matronics.com>
>>> [mailto:owner-rv10-list-server@matronics.com
>>> <mailto:owner-rv10-list-server@matronics.com>] On Behalf Of
>>> Berck E. Nash
>>> Sent: Monday, April 20, 2015 12:44 AM
>>> To: rv10-list@matronics.com <mailto:rv10-list@matronics.com>
>>> Subject: Re: RV10-List: Fuel Return Line Location?
>>>
>>> <flyboy@gmail.com <mailto:flyboy@gmail.com>>
>>>
>>> I'm leaning toward a duplex valve, but I'm also considering
>>> two fuel valves,
>>> one for the source and one for the return. This isn't that
>>> different than
>>> jets I've flown, and I think I can handle the "complexity".
It's cheaper
>>> and it gives the advantage of being able to transfer fuel,
>>> which might come
>>> in handy. Regardless, none of the answers so far tell me
>>> where to tap the
>>> return line:)
>>>
>>>
>>>
>>>
>>> *
>>>
>>> D============================================
>>> List"">http://www.matronics.com/Navigator?RV10-List
>>> D============================================
>>> //forums.matronics.com <http://forums.matronics.com>
>>> D============================================
>>> ot;">http://www.matronics.com/contribution
>>> D============================================
>>>
>>> *
>>
>> *
>>
>> get="_blank">http://www.matronics.com/Navigator?RV10-List
>> tp://forums.matronics.com
>> _blank">http://www.matronics.com/contribution
>>
>> *
>>
>>
>> *
>>
>>
>> *
>
>
>
>
>
Message 2
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| Subject: | Re: Fuel Return Line Location? |
O2 sensors do not burn out, with or without lead. They get coated/fouled
by the lead which destroys their sensitivity very quickly. The period to
sensor failure is typically less than a dozen hours when exposed to
leaded fuel. That is my experience over 30 yrs of working on auto
emission control systems.
The total improvement available with optimizing mixture and spark
control is on the order of 5-10 percent. Whether that is significant or
not is your call. I see claims for more, without significant data to
back them up.
An RSA5 system and magnetos can be overhauled for less than 1/2 what
this system costs. But then you have to add in the cost of adding dual
alternators, dual buss, dual batteries and the cost of maintaining those
extras so as to ensure your risk of failure is as near nil as possible.
You are on the wrong track talking air to fuel ratios in an aircraft
engine. You have 6 different air paths to cylinders. Those intake tubes
are only crudely "tuned" and are not equal length. You have six
different cylinders, each with their own fuel to air ratio. An oxygen
sensor is only going to measure an average of 3 cylinders, unless you
somehow tie together the exhaust from all six with a non-stock exhaust
system. Then you would be averaging six into one, which tells you
nothing about how the individual cylinders are doing. EGT is very good
at measuring mixture in relation to the other cylinders. If a system
could ensure that all six cylinders achieved peak EGT within 0.2 gal
fuel flow of each other, then you would have something. It is the
balancing of the mixtures that safely allows operating lean of peak, so
that each cylinder is producing the same power. It is the difference in
power that causes roughness, not the old wive's tale of "lean misfire".
There is no question that it is safer to run an engine lean of peak EGT
than the mixture you are suggesting. Running LOP let the airlines extend
the TBO on their R3350 engines to more than triple the original TBO.
Valve distress comes from operating too rich and too hot, in the area of
30-80 ROP, not from running lean of peak.
It has taken the auto industry 50 yrs to develop very good mixture and
spark control. It also required unleaded fuel. That was with tens of
thousands of dyno hours and huge investment in engineering and computer
development to map optimal spark/mixture combinations for each load. To
think you are going to patch together some of that technology and
achieve the same thing in an aircraft engine running leaded fuel with
minimal R&D is a big gamble. Same as there are a few successful auto
engines running in aircraft, but many more conversions that have not
worked. That this system apparently needs some mapping of mixture
indicates that it is not fully developed.
On 4/20/2015 11:56 PM, Justin Jones wrote:
>
> The wide band O2 sensors will eventually burn out due to lead fowling. They are
pricey, and it does not happen in less than one tank of 100LL. There are many
guys that have used them for tuning and removed them when they are done with
them. Not a good idea to keep them in as they will eventually burn out completely.
If you plan on changing your fuel map, I would HIGHLY suggest using a
wide band sensor and a display to ensure your AFR (air fuel ratio) is not getting
to lean. The stoichiometric ratio for a natural aspirated engine is 14.7:1
It is safer in our aircraft engines to run them at 13.7:1 and thats what the
EFII systems stock fuel map is programed to provide. Another indicator of
the AFR is EGT, but other things can affect EGT, so the safe bet while tuning
is to use a wide band O2 sensor and an AFR gauge to display the correct number
to ensure you dont get too lean.
>
> The EFII system for me, was a cost benefit to overhauling what I currently had.
An RSA5 fuel injection overhaul, new fuel pump, new mags, wires, plugs etc
would have been at or above the cost of acquisition of the EFiI system. I have
heard nothing but good from this system and Robert Paisley from ProTec Performance
has been nothing short of a rockstar with his customer service. I would
agree that more benefit comes from the EI than the fuel injection, but by modulating
the injectors, they are seeing gains on the dyno with the Electronic
Fuel Injection over the mechanical injection. Also of note, the Lycoming hot
start issue disappears with the EFII fuel injection. Mixture management is simple
with the EFII system due to the programed fuel map they have in the ECUs.
It reads the Manifold pressure, RPM, Throttle position sensor, and comes up
with the fuel demand for the engine regardless of altitude. There is NO MAF
sensor in this system. It uses a similar sensor in !
> the throttle body. If you wish to trim fuel to change the EGTs, you can do
so with the mixture rheostat, or you can do it by reprograming the ECUs fuel
mapping. Takes some programing knowledge and the software, but its not hard to
do. Robert Paisley and or SDS can help with this as well. There is significant
fuel savings with this system, but as Kelly stated, it is not half the fuel.
>
> Robert has his EFII system on numerous aircraft that race in the Reno air races,
as well as many many happy customers flying the complete system. The ECUs
are SDS ECUs and have hundreds of thousands of hours tested on them. The fuel
pumps are automotive type, and there are 2 of them. Tons of proving time on the
fuel pumps as well. The Coils are similar (if not the same) as the one from
a Subaru Impreza. Again, hundreds of thousands of hours on the coils as well.
The spark plugs are iridium automotive plugs and are a fraction of the price
as an aircraft plug and out perform them as well. I feel perfectly safe with
the EFII system in my aircraft, and would recommend them to anyone who wants
a traditional aircraft engine with a modern fuel and ignition system.
>
> Hope this helps!
>
> Justin
>
>
> On Apr 20, 2015, at 11:43 AM, Kelly McMullen <kellym@aviating.com> wrote:
>>
>> I assume you are aware that leaded fuel such as 100LL will destroy an oxygen
sensor in less than one tank of fuel?
>> I seriously doubt that the EFII system and the dual everything required to ensure
it has power to work will save enough fuel to have a payback in any reasonable
time frame. Mixture management on conventional fuel injection with magnetos
is childs play once you get the system delivering equal fuel mixture to each
cylinder. While autos are using less gas and producing more power, they are
doing it with higher compression ratios, knock sensors and thousands of hours
of dyno time. Most of the incremental benefit comes from electronic ignition,
not electronic timed fuel injection. Feel free to experiment, but don't expect
to get equal power on half the gas, or half the workload, for equal investment.
>>
>> On 4/20/2015 9:55 AM, Berck E. Nash wrote:
>>> Since the fuel is metered directly at the injectors by the ECU, why do you
have to mess with the mixture knob? The EFII website says, "Automatic mixture
control (no mixture knob to fool with)", but you're saying that's not entirely
true? Is the issue that you're compensating for a lack of initial ECU programming
by altering the fuel pressure until the you get the programming dialed
in? Since the system has a MAP and IAT sensor, it seems like it should be able
to meter correctly without any input from the pilot. It doesn't look like
the EFII includes an oxygen sensor, though?
>>>
>>> Any idea if there are plans to fly this plane on automotive gasoline?
>>>
>>>
>>>
>>>
>>> On Mon, Apr 20, 2015 at 10:38 AM, Jesse Saint <jesse@saintaviation.com <mailto:jesse@saintaviation.com>> wrote:
>>>
>>> I think you're kidding yourself if you think there is no mixture
>>> to worry about. I spend more time on the mixture knob so far than
>>> I do on the mixture control with a standard system. It's possible
>>> that once you get things all tuned up the way you want them you
>>> may not use it as much, but I really don't use it that much on a
>>> standard system either. I lean a little as I climb, then I set
>>> power, rpm and fuel flow for cruise.
>>>
>>> I would imagine if you are burnin 12gph, you are probably
>>> returning at least that much to the tank, if not more. I wouldn't
>>> want to have to mess with picking a return tank separate from a
>>> feed tank. There are warnings when your fuel in a tank gets low,
>>> but I don't know of a warning saying your tank is getting too
>>> full. If you get busy or get bored and aren't managing fuel with a
>>> normal system, you will get something yelling at you saying you're
>>> getting into the red on the draw tank, but it won't happen if you
>>> start to pump it overboard through the return tank vent.
>>>
>>> I agree that electric ignition is tried and true in cars, but so
>>> far there are a total of 10 fleet hours in the RV-10 with a full
>>> EFII system and thousands and thousands with mags and standard
>>> fuel injection. Far from a no-brainier in my book unless you are
>>> talking the other way around.
>>>
>>> Jesse Saint
>>> Saint Aviation, Inc.
>>> 352-427-0285 <tel:352-427-0285>
>>> jesse@saintaviation.com <mailto:jesse@saintaviation.com>
>>>
>>> Sent from my iPad
>>>
>>> On Apr 20, 2015, at 11:58 AM, Berck E. Nash <flyboy@gmail.com
>>> <mailto:flyboy@gmail.com>> wrote:
>>>
>>>> Carl- thanks so much for the picture. I'll plan on the same
>>>> location. As for the cost: We haven't purchased anything yet,
>>>> and probably won't until we source an engine. Hoping available
>>>> systems will only get cheaper, but cursory research indicates
>>>> it'll cost not much more than more conventional FI and ignition
>>>> setups.
>>>>
>>>> Jesse- Thanks for the heads up. Glad to hear that one is flying
>>>> already, and I hope you'll keep us updated of any gotchas. After
>>>> seeing that an EFII system is available, I can't imagine not
>>>> using it. I'm aware of the need for a fully redundant electrical
>>>> system and dual ECU's. I was already planning on dual electronic
>>>> ignition and the dual alternators that necessitates, so
>>>> electronic fuel injection only makes sense to me. This is, I
>>>> think, the beauty of building an experimental-- the ability to
>>>> use "modern" (30-year-old tried-and-tested) technology in an
>>>> airplane, instead of being forced to rely on a fuel delivery
>>>> system from the 1950's.
>>>>
>>>> Any RV-10 specific EFII links, information, vendor tips, etc,
>>>> would be greatly appreciated.
>>>>
>>>> As for the "complexity" of a fuel return tank selection, it seems
>>>> a bit silly to me that choosing a return tank is considered
>>>> "overly complex." It's the difference of switching two valves
>>>> instead of one when you switch tanks in normal operations. Sure,
>>>> it's more complex than a single knob, but I'm used to much more
>>>> complicated fuel systems many of which require deliberate
>>>> knowledge of the fuel return tank. I'm not really concerned
>>>> about it either way. The only reason to want to transfer fuel
>>>> would be a leak, and in most situations, getting on the ground
>>>> quickly makes a lot more sense than moving fuel around. Since I
>>>> won't have to worry about the insane complexity of a mixture
>>>> control, I can use those saved neurons to handle the fuel return
>>>> tank if I wind up with two valves.
>>>>
>>>> On Mon, Apr 20, 2015 at 7:49 AM, Carl Froehlich
>>>> <carl.froehlich@verizon.net <mailto:carl.froehlich@verizon.net>>
>>>> wrote:
>>>>
>>>> Berck,
>>>>
>>>> I added a 1/4" purge line return to the left tank when
>>>> building in case I
>>>> ended up with an AFP injection system (photo attached). This
>>>> is the same
>>>> location I used the RV-8A which had AFP injection.
>>>>
>>>> Adding a return line is straight forward and if you get the
>>>> fitting in about
>>>> the same area as the vent line connection you should not have
>>>> an issue. I'd
>>>> keep it high (like my photo) so that it is away from the fuel
>>>> pick up -
>>>> should help with pulling cooler fuel into the engine as
>>>> compared to the
>>>> hotter return fuel.
>>>>
>>>> Just curious - how much did this EFII system cost?
>>>>
>>>> Carl
>>>>
>>>> -----Original Message-----
>>>> From: owner-rv10-list-server@matronics.com
>>>> <mailto:owner-rv10-list-server@matronics.com>
>>>> [mailto:owner-rv10-list-server@matronics.com
>>>> <mailto:owner-rv10-list-server@matronics.com>] On Behalf Of
>>>> Berck E. Nash
>>>> Sent: Monday, April 20, 2015 12:44 AM
>>>> To: rv10-list@matronics.com <mailto:rv10-list@matronics.com>
>>>> Subject: Re: RV10-List: Fuel Return Line Location?
>>>>
>>>> <flyboy@gmail.com <mailto:flyboy@gmail.com>>
>>>>
>>>> I'm leaning toward a duplex valve, but I'm also considering
>>>> two fuel valves,
>>>> one for the source and one for the return. This isn't that
>>>> different than
>>>> jets I've flown, and I think I can handle the "complexity".
It's cheaper
>>>> and it gives the advantage of being able to transfer fuel,
>>>> which might come
>>>> in handy. Regardless, none of the answers so far tell me
>>>> where to tap the
>>>> return line:)
>>>>
>>>>
>>>>
>>>>
>>>> *
>>>>
>>>> D============================================
>>>> List"">http://www.matronics.com/Navigator?RV10-List
>>>> D============================================
>>>> //forums.matronics.com <http://forums.matronics.com>
>>>> D============================================
>>>> ot;">http://www.matronics.com/contribution
>>>> D============================================
>>>>
>>>> *
>>> *
>>>
>>> get="_blank">http://www.matronics.com/Navigator?RV10-List
>>> tp://forums.matronics.com
>>> _blank">http://www.matronics.com/contribution
>>>
>>> *
>>>
>>>
>>> *
>>>
>>>
>>> *
>>
>>
>>
>>
>
>
Message 3
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|
| Subject: | Re: Fuel Return Line Location? |
You can still run LOP with the EFII system. It just does not do it automatically.
There is a rheostat that precisely adjusts pulse width. You just watch your
egts like you usually would.
> On Apr 21, 2015, at 06:37, Kelly McMullen <kellym@aviating.com> wrote:
>
>
> O2 sensors do not burn out, with or without lead. They get coated/fouled by the
lead which destroys their sensitivity very quickly. The period to sensor failure
is typically less than a dozen hours when exposed to leaded fuel. That is
my experience over 30 yrs of working on auto emission control systems.
> The total improvement available with optimizing mixture and spark control is
on the order of 5-10 percent. Whether that is significant or not is your call.
I see claims for more, without significant data to back them up.
> An RSA5 system and magnetos can be overhauled for less than 1/2 what this system
costs. But then you have to add in the cost of adding dual alternators, dual
buss, dual batteries and the cost of maintaining those extras so as to ensure
your risk of failure is as near nil as possible.
> You are on the wrong track talking air to fuel ratios in an aircraft engine.
You have 6 different air paths to cylinders. Those intake tubes are only crudely
"tuned" and are not equal length. You have six different cylinders, each with
their own fuel to air ratio. An oxygen sensor is only going to measure an average
of 3 cylinders, unless you somehow tie together the exhaust from all six
with a non-stock exhaust system. Then you would be averaging six into one, which
tells you nothing about how the individual cylinders are doing. EGT is very
good at measuring mixture in relation to the other cylinders. If a system could
ensure that all six cylinders achieved peak EGT within 0.2 gal fuel flow
of each other, then you would have something. It is the balancing of the mixtures
that safely allows operating lean of peak, so that each cylinder is producing
the same power. It is the difference in power that causes roughness, not
the old wive's tale of "lean misfire". There is no question that it is safer
to run an engine lean of peak EGT than the mixture you are suggesting. Running
LOP let the airlines extend the TBO on their R3350 engines to more than triple
the original TBO. Valve distress comes from operating too rich and too hot,
in the area of 30-80 ROP, not from running lean of peak.
> It has taken the auto industry 50 yrs to develop very good mixture and spark
control. It also required unleaded fuel. That was with tens of thousands of dyno
hours and huge investment in engineering and computer development to map optimal
spark/mixture combinations for each load. To think you are going to patch
together some of that technology and achieve the same thing in an aircraft engine
running leaded fuel with minimal R&D is a big gamble. Same as there are
a few successful auto engines running in aircraft, but many more conversions that
have not worked. That this system apparently needs some mapping of mixture
indicates that it is not fully developed.
>
>> On 4/20/2015 11:56 PM, Justin Jones wrote:
>>
>> The wide band O2 sensors will eventually burn out due to lead fowling. They
are pricey, and it does not happen in less than one tank of 100LL. There are
many guys that have used them for tuning and removed them when they are done with
them. Not a good idea to keep them in as they will eventually burn out completely.
If you plan on changing your fuel map, I would HIGHLY suggest using
a wide band sensor and a display to ensure your AFR (air fuel ratio) is not getting
to lean. The stoichiometric ratio for a natural aspirated engine is 14.7:1
It is safer in our aircraft engines to run them at 13.7:1 and thats what
the EFII systems stock fuel map is programed to provide. Another indicator of
the AFR is EGT, but other things can affect EGT, so the safe bet while tuning
is to use a wide band O2 sensor and an AFR gauge to display the correct number
to ensure you dont get too lean.
>> The EFII system for me, was a cost benefit to overhauling what I currently
had. An RSA5 fuel injection overhaul, new fuel pump, new mags, wires, plugs etc
would have been at or above the cost of acquisition of the EFiI system. I
have heard nothing but good from this system and Robert Paisley from ProTec Performance
has been nothing short of a rockstar with his customer service. I would
agree that more benefit comes from the EI than the fuel injection, but by
modulating the injectors, they are seeing gains on the dyno with the Electronic
Fuel Injection over the mechanical injection. Also of note, the Lycoming hot
start issue disappears with the EFII fuel injection. Mixture management is
simple with the EFII system due to the programed fuel map they have in the ECUs.
It reads the Manifold pressure, RPM, Throttle position sensor, and comes
up with the fuel demand for the engine regardless of altitude. There is NO MAF
sensor in this system. It uses a similar sensor i!
> n !
>> the throttle body. If you wish to trim fuel to change the EGTs, you can do
so with the mixture rheostat, or you can do it by reprograming the ECUs fuel
mapping. Takes some programing knowledge and the software, but its not hard to
do. Robert Paisley and or SDS can help with this as well. There is significant
fuel savings with this system, but as Kelly stated, it is not half the fuel.
>>
>> Robert has his EFII system on numerous aircraft that race in the Reno air races,
as well as many many happy customers flying the complete system. The ECUs
are SDS ECUs and have hundreds of thousands of hours tested on them. The fuel
pumps are automotive type, and there are 2 of them. Tons of proving time on
the fuel pumps as well. The Coils are similar (if not the same) as the one from
a Subaru Impreza. Again, hundreds of thousands of hours on the coils as well.
The spark plugs are iridium automotive plugs and are a fraction of the price
as an aircraft plug and out perform them as well. I feel perfectly safe with
the EFII system in my aircraft, and would recommend them to anyone who wants
a traditional aircraft engine with a modern fuel and ignition system.
>>
>> Hope this helps!
>>
>> Justin
>>
>>
>>
>>> On Apr 20, 2015, at 11:43 AM, Kelly McMullen <kellym@aviating.com> wrote:
>>>
>>> I assume you are aware that leaded fuel such as 100LL will destroy an oxygen
sensor in less than one tank of fuel?
>>> I seriously doubt that the EFII system and the dual everything required to
ensure it has power to work will save enough fuel to have a payback in any reasonable
time frame. Mixture management on conventional fuel injection with magnetos
is childs play once you get the system delivering equal fuel mixture to
each cylinder. While autos are using less gas and producing more power, they are
doing it with higher compression ratios, knock sensors and thousands of hours
of dyno time. Most of the incremental benefit comes from electronic ignition,
not electronic timed fuel injection. Feel free to experiment, but don't expect
to get equal power on half the gas, or half the workload, for equal investment.
>>>
>>>> On 4/20/2015 9:55 AM, Berck E. Nash wrote:
>>>> Since the fuel is metered directly at the injectors by the ECU, why do you
have to mess with the mixture knob? The EFII website says, "Automatic mixture
control (no mixture knob to fool with)", but you're saying that's not entirely
true? Is the issue that you're compensating for a lack of initial ECU programming
by altering the fuel pressure until the you get the programming dialed
in? Since the system has a MAP and IAT sensor, it seems like it should be able
to meter correctly without any input from the pilot. It doesn't look like
the EFII includes an oxygen sensor, though?
>>>>
>>>> Any idea if there are plans to fly this plane on automotive gasoline?
>>>>
>>>>
>>>>
>>>>
>>>> On Mon, Apr 20, 2015 at 10:38 AM, Jesse Saint <jesse@saintaviation.com <mailto:jesse@saintaviation.com>> wrote:
>>>>
>>>> I think you're kidding yourself if you think there is no mixture
>>>> to worry about. I spend more time on the mixture knob so far than
>>>> I do on the mixture control with a standard system. It's possible
>>>> that once you get things all tuned up the way you want them you
>>>> may not use it as much, but I really don't use it that much on a
>>>> standard system either. I lean a little as I climb, then I set
>>>> power, rpm and fuel flow for cruise.
>>>>
>>>> I would imagine if you are burnin 12gph, you are probably
>>>> returning at least that much to the tank, if not more. I wouldn't
>>>> want to have to mess with picking a return tank separate from a
>>>> feed tank. There are warnings when your fuel in a tank gets low,
>>>> but I don't know of a warning saying your tank is getting too
>>>> full. If you get busy or get bored and aren't managing fuel with a
>>>> normal system, you will get something yelling at you saying you're
>>>> getting into the red on the draw tank, but it won't happen if you
>>>> start to pump it overboard through the return tank vent.
>>>>
>>>> I agree that electric ignition is tried and true in cars, but so
>>>> far there are a total of 10 fleet hours in the RV-10 with a full
>>>> EFII system and thousands and thousands with mags and standard
>>>> fuel injection. Far from a no-brainier in my book unless you are
>>>> talking the other way around.
>>>>
>>>> Jesse Saint
>>>> Saint Aviation, Inc.
>>>> 352-427-0285 <tel:352-427-0285>
>>>> jesse@saintaviation.com <mailto:jesse@saintaviation.com>
>>>>
>>>> Sent from my iPad
>>>>
>>>> On Apr 20, 2015, at 11:58 AM, Berck E. Nash <flyboy@gmail.com
>>>> <mailto:flyboy@gmail.com>> wrote:
>>>>
>>>>> Carl- thanks so much for the picture. I'll plan on the same
>>>>> location. As for the cost: We haven't purchased anything yet,
>>>>> and probably won't until we source an engine. Hoping available
>>>>> systems will only get cheaper, but cursory research indicates
>>>>> it'll cost not much more than more conventional FI and ignition
>>>>> setups.
>>>>>
>>>>> Jesse- Thanks for the heads up. Glad to hear that one is flying
>>>>> already, and I hope you'll keep us updated of any gotchas. After
>>>>> seeing that an EFII system is available, I can't imagine not
>>>>> using it. I'm aware of the need for a fully redundant electrical
>>>>> system and dual ECU's. I was already planning on dual electronic
>>>>> ignition and the dual alternators that necessitates, so
>>>>> electronic fuel injection only makes sense to me. This is, I
>>>>> think, the beauty of building an experimental-- the ability to
>>>>> use "modern" (30-year-old tried-and-tested) technology in an
>>>>> airplane, instead of being forced to rely on a fuel delivery
>>>>> system from the 1950's.
>>>>>
>>>>> Any RV-10 specific EFII links, information, vendor tips, etc,
>>>>> would be greatly appreciated.
>>>>>
>>>>> As for the "complexity" of a fuel return tank selection, it seems
>>>>> a bit silly to me that choosing a return tank is considered
>>>>> "overly complex." It's the difference of switching two valves
>>>>> instead of one when you switch tanks in normal operations. Sure,
>>>>> it's more complex than a single knob, but I'm used to much more
>>>>> complicated fuel systems many of which require deliberate
>>>>> knowledge of the fuel return tank. I'm not really concerned
>>>>> about it either way. The only reason to want to transfer fuel
>>>>> would be a leak, and in most situations, getting on the ground
>>>>> quickly makes a lot more sense than moving fuel around. Since I
>>>>> won't have to worry about the insane complexity of a mixture
>>>>> control, I can use those saved neurons to handle the fuel return
>>>>> tank if I wind up with two valves.
>>>>>
>>>>> On Mon, Apr 20, 2015 at 7:49 AM, Carl Froehlich
>>>>> <carl.froehlich@verizon.net <mailto:carl.froehlich@verizon.net>>
>>>>> wrote:
>>>>>
>>>>> Berck,
>>>>>
>>>>> I added a 1/4" purge line return to the left tank when
>>>>> building in case I
>>>>> ended up with an AFP injection system (photo attached). This
>>>>> is the same
>>>>> location I used the RV-8A which had AFP injection.
>>>>>
>>>>> Adding a return line is straight forward and if you get the
>>>>> fitting in about
>>>>> the same area as the vent line connection you should not have
>>>>> an issue. I'd
>>>>> keep it high (like my photo) so that it is away from the fuel
>>>>> pick up -
>>>>> should help with pulling cooler fuel into the engine as
>>>>> compared to the
>>>>> hotter return fuel.
>>>>>
>>>>> Just curious - how much did this EFII system cost?
>>>>>
>>>>> Carl
>>>>>
>>>>> -----Original Message-----
>>>>> From: owner-rv10-list-server@matronics.com
>>>>> <mailto:owner-rv10-list-server@matronics.com>
>>>>> [mailto:owner-rv10-list-server@matronics.com
>>>>> <mailto:owner-rv10-list-server@matronics.com>] On Behalf Of
>>>>> Berck E. Nash
>>>>> Sent: Monday, April 20, 2015 12:44 AM
>>>>> To: rv10-list@matronics.com <mailto:rv10-list@matronics.com>
>>>>> Subject: Re: RV10-List: Fuel Return Line Location?
>>>>>
>>>>> <flyboy@gmail.com <mailto:flyboy@gmail.com>>
>>>>>
>>>>> I'm leaning toward a duplex valve, but I'm also considering
>>>>> two fuel valves,
>>>>> one for the source and one for the return. This isn't that
>>>>> different than
>>>>> jets I've flown, and I think I can handle the "complexity".
It's cheaper
>>>>> and it gives the advantage of being able to transfer fuel,
>>>>> which might come
>>>>> in handy. Regardless, none of the answers so far tell me
>>>>> where to tap the
>>>>> return line:)
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> *
>>>>>
>>>>> D============================================
>>>>> List"">http://www.matronics.com/Navigator?RV10-List
>>>>> D============================================
>>>>> //forums.matronics.com <http://forums.matronics.com>
>>>>> D============================================
>>>>> ot;">http://www.matronics.com/contribution
>>>>> D============================================
>>>>>
>>>>> *
>>>> *
>>>>
>>>> get="_blank">http://www.matronics.com/Navigator?RV10-List
>>>> tp://forums.matronics.com
>>>> _blank">http://www.matronics.com/contribution
>>>>
>>>> *
>>>>
>>>>
>>>> *
>>>>
>>>>
>>>> *
>
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| Subject: | Re: Fuel Return Line Location? |
I am building a -10 and WILL be using the complete EFII system.
That being said, I find it somewhat humorous how this thread is developing.
On one hand you have the "that's the way we have always done it" crowd.
On the other hand, there are the guys who want to bring our sport/hobby/obsession
into the 21st century.
There will NEVER be agreement between the two sides but consider this:
If no one ever questioned Mr. Ford, we would all be driving black cars. If no
one ever question the points and condenser system, we would not have electronic
ignition. How about carbs versus FI? Steam gauges versus EFIS?
It goes on and on. There are those that want to progress forward and there are
those who are more comfortable with the ancient technology of the last century.
It is what is great about experimental aircraft...
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=441110#441110
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