I plan on experimenting with the low pressure dribble fuel injection
system. I have the pix of the 1/8" miniature regulator you shared with
the list. I found what looks like the one you mentioned at McMaster Carr
(# 6763K11), but it is the relieving style so it vents if the regulated
side exceeds the selected pressure. NOT GOOD for fuel to be vented!
Can you tell me the source for the regulator in the pix?
Doc Custer
Retired Software Engineer and sometime Audiologist
It is this little jewel right Doc?
It has three pipe threaded ports so you plumb the return flow
back to the fuel tank exactly what must be done using
Tracy's EFI system. The only ones that don't do this are the
computer controlled PWM fuel pumps.
---------------------------------------
This message triggered an idea Doc. A combination of
EFI and the low pressure dribble system. Since one needs
a low pressure electric fuel pump no matter what control the pump
pressure PWM
(Assuming electric fuel pump for 13B?) Yes and all low wing
airplanes.
with a 44 cent
PIC microcomputer that takes data in
from a MAP sensor,
(Manifold Air press-what sensor is used/specified?). Free Scale.
RPM and a leaning knob pot on the instrument
panel.
To quote Don Lancaster:
"The PIC microprocessor from Microchip Technology has now
become the hardware component of the decade. To the point
where it is laughingly absurd to ever again use a 555 timer."
Voila!!! Super simple low pressure EFI!!!! The PIC has an A to D
for the MAP sensor and leaning knob and an interrupt
for the RPM. Should take all of an hour to write the BASIC
program :)
(leaning knob interface is mechanical or analog sensor
with A/D to PIC? Yes
Potentiometer? Variable resister.
Is this all written in "BASIC"? Can be.
If so a good book to learn BASIC - No, I never did
learn it. It varies with the version. The docs come
with the language program.
No injectors. Small holes in the p-port slide throttle
instead.
This is the slide throttle outlined/depicted on your
website, right? Correct.
No injector wires in the cowl to burn. Only wires go
to the low cost, low pressure, off the shelf fuel pump.
No leaning needle valve. No metering ramp in the slide throttle
or multiple holes. Just one small hose
So the drawing on the website will change??? Correct.
There is a small hose to the MAP sensor
is this an analog transducer of some sort?? Correct
mounted on the PIC PC board which
is just behind the panel with the PC board mounted leaning
pot shaft sticking through the panel.
If you want to spend a bit more than 44 cents on the PIC
is this an electronic board with I/O? No. The I/O is on
the chip.
44cents??? Just for the chip.
you can
add a USB data acquisition interface and download the flash stored
historical data to a PC. Since THE pic knows the fuel flow it knows
the GPH. Since the PIC knows the GPH and it could take NEMA 0183
ASCII data in from a GPS and calculate and display the MPG IN
REAL TIME!!!!
Handy for checking winds aloft.
Now if you add the clutch throw out bearing dyno you could
display REAL TIME HP and BSFC.
Ive read the website and still don't know what this means?
Tracy should be doing this anyway
since he is building both the PSRU and the EFI.
This is probably the best idea I have had in the last
couple of years if I do say so myself :)
BTW Sorry corporation. You can't patent it as I have
published it here first.
Paul Lamar ...No rotor no motor.
Ok guys. I know I need to read SOMETHING X 4 to just get a clue about
what you are discussing here. Please refer me to what I must read/study
to understand some/most of what's written below. I know a little
programming as I did some PLC programming in the 80's and early 90's.
(That's what getting promoted to management does for one's technical
skills). I have never been an automotive type (read engines). So any
help with some general understanding and roadmaps to in depth (not too
deep please) study of the EFI system(s) specifically for the rotoray
engine in "our" aeronautical application. I rebuilt a Dodge slant six
in my 1975 pickup because I couldn't afford to do anything else. I've
built lots of "things". Homes, apartments, strip centers, sailboats and
control systems for chemical plants and refineries, so I can understand
the above average technical jargon given the available reference
material. I understand A to D and boolean logic although some of the
symbols in your attachment are new (or did I just forget?) to me. ANY
help would be appreciated as I need to be able to understand this
stuff. I've also made notations in the text below as to what I know and
what I don't. I'm also a member of the "Glass Panel Group"
http://groups.yahoo.com/group/GlassPanel/ where I'm trying to learn how
to build my own "GPS Moving Map" and other stuff.
Allen Slominski
Houston, TX
(Uneducated and Thirsty for Knowledge)
We will start with a glossary.
PIC Very cheap single chip microcomputer from Microchip Inc.
GPH: Gallons Per Hour.
MAP: Manifold Air Pressure. No air zero power. 30 inches of
Hg full power.
EFI: Electronic Fuel Injection. Now standard on all cars.
BSFC: Brake Specific Fuel Consumption. A measure of how much
HP is generated in one hour per pound of fuel burned in one hour.
A gallon weighs six pounds.
ASCII: data. American Society ???? I forgot. All the letters
of the alphabet and the numbers 0 to 9. Basically what you
have on your keyboard. There are standard binary codes assigned
to each letter or number. ASCII data is human readable as opposed
to ones and zeros computer data.
PWM: Pulse Width Modulation. A means of controlling the
speed of an electric motor. The wider the pulse the
more juice the motor gets and the faster it goes.
the number of pulses per second have nothing to do
with it other than making it seem smoother.
MPH: Miles Per Hour.
GPS: Global Position Satellite
NEMA 0183: National Electronic Marine Association a standard means
of having GPS's talk to other devices like auto pilots
and personal computers through just 3 wires called an RS232
serial interface. The data comes out in ASCII form
and in a specified order. Time first, MPH second, Latitude third,
etc., etc., etc..
BASIC: Simple programming language. Can be written in BASIC
as there are BASIC compilers and interpreters for the PIC.
REAL TIME: Happening as we speak. In other words if you talk
to your computer and the computer understands some how and
the words appear on the screen immediately as you are speaking
then that is real time. If it happens several minutes later that
is not Real Time. If the PIC is connected to a PC and the fuel
pump motor pulse width, the engine RPM and the manifold pressure
data comes out in a continuous stream from a USB port then that
is Real Time.
POT: A variable resistor or potentiometer.
A/D: Analog to Digital converter. A leaning potentiometer
has three wires. The top wire is connected to five volts
the bottom wire is connected to ground. The center wire
contacts the resistor some where along its length. As you
turn the shaft some voltage between zero to five volts
is seen on that 3rd wire. That is called analog data.
An 8 bit A/D converts that analog data to a binary number
between zero and 256.
Clutch throw out bearing dyno: A method of measuring the
torque on a helical gear set using an annular hydraulic cylinder
that surrounds the input shaft to a PSRU. Annular hydraulic
cylinders are widely used in passenger cars and truck to throw
the clutch out of engagement (Invented by me 35 years ago:))
If you know the torque and the RPM you know the horsepower.
Use the search function in your email program to search
old messages for more info on this subject. You have been
saving them have you not? :)
Did I miss anything? Any more questions along these lines?
Google is also a big help on this stuff.
There is a magazine at some book stores called Nut & Volts.
Great for learning about this sort of PIC stuff.
Paul Lamar ...No rotor no motor.
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