snipes:

The airplane operating requirements are relatively simple
compared to
that of a performance car like a Corvette. In the
Corvette, they want
good throttle response at all RPM, and good fuel economy
with very
minimal driver involvement - one lever. On the other hand,
the
airplane really has only a couple of requirements.. It
can't quit.
It can't burn too much fuel in cruise. It has to make
the peak
horsepower afforded by the mechanical limits of the engine.
That's
not too bad by comparison. The airplane engine doesn't
have to idle
all that well as long as it doesn't actually quit. It
can have a
separate lever for controlling power vs. economy. All of
this makes
the tunability of the airplane easier to accomplish by
comparison.

As far as running the engine on the dyno, I think that was
a p-port,
and it was being run with the manifold pressure tap located
at the
wrong place on the engine for good readings. It would be
interesting
to hop on the dyno with the mp tap installed in the housing
and see
how the tuning goes.


Regards,

Matt-

Looks fixed to me. This looks fine.

Paul Lamar


Wonderful response Bill. I would add that the choice
between carb, mech
fi,
efi, distributor, dis, etc boils down to not only
simplicity but also
cost.
This wouldn't be the case in the certified market but
since we don't
have
to
jump hops for the FAA, we can choose our options based on
more than
just a
certificate. With regards to fuel delivery, it seems like
the only two
cost
effective options are the Holley and custom efi (555,
Tracy's,
Megasquirt.)
If someone could find a better carb in terms of function
and cost, that
would be cool but at this point that seems very unlikely.
Mech fi
would be
a
very good feature if it wasn't SO expensive. For $2900
I could buy a
Motec
(read $$$) and still have money left for dyno tuning. While
custom efi
would
be the holy grail of performance and flexibility, how many
people
really
need it? The turbocharged and the aerobatic (are there any
using
Mazda's?)
could genuinely use them, for everyone else, seems
unlikely.
Vlad
--


My problem with electronic FI is in the systems support..
Requires
independent, redundant power (dual alternators), and high
pressure
fuel. Not insurmountable by any means, but I'm not
convinced the
payoff is worth it for what I want to be flying.


Matt-

It's part of the risk that one must accept when
building or flying an
experimental aircraft or using a non-certified engine. Am
I against
making
the systems safer and less likely to cause a catastrophic
failure, no.
But
I'm not asking an engine from a car to be as redundant
and rudimentary
(read
safe) in design as a $25k+ aero engine. Would I fly an efi
rotary with a
single alternator, battery, ecu, etc., yes. If I was that
concerned about
safety, I would get a certified slug and call it a day.
Vlad

To interject a disrupting thought. I have a Bosch CIS fuel
injection
running on a rotary in an airplane. Al thought the plane
has not flown(
a problem with me not the plane), the injection was
extensively tested
on the ground on a test stand. The CIS is a mass flow
sensor with
automatic mixture adjustment. In addition the mixture can
be
modified to any level from too rich to run to too lean to
run. All the
hard work of air verses fuel has been done at time of
manufacture of the
unit.
The units are very inexpensive from a junk yard. I have
several that I
have used on cars that were no where worn out. A little
clean up and
they work perfectly.
However they are not without problems.
1. Size is a problem.
2. High pressure fuel.
3.Weight might be a problem. They are not light because of
the cast iron
fuel distributor.

C Smale

I was going through my records, the MAF I purchased new from Rock Auto was
$61, ('02 5.4l V8) didn't have to hunt through junk yard, just type on
keyboard, no time spent removing, or driving to junk yard, or cleaning and
reconditioning. ABS sensors, $22 ea, same conditions, with added benefit of
not laying on my back in the mud or getting crud in my face removing them.

Time spent researching part numbers and tracking down flow data for suitable
injectors so far I've put in maybe 4-5 hrs. I have decided it is easier to
just buy some 42 lb ford racing injectors(known qualities), set of 8 for
$210, that's $26.25 ea. free shipping. Anyone want the other 4?
That's under $300 so far. I figure, maybe another $200 for the rest of the
electronic 555 parts and circuit boards. Fuel runner and regulator, haven't
priced yet, can't be that much.
I figure the rest of the intake stuff like tubes and slide throttle would be
necessary no matter how you skinned the P-Port cat, so those costs are
comparably the same.

Because of differences in the MAF and injectors anyone decides to use(or
carburators, and differences in how you make your induction setup), I agree
that anyone choosing to go rotary should be prepared to put in tuning time.
Everyone has to do it, so it is not a differentiating factor. I REALLY like
the FI systems resistance to icing.
I dont think hardening the electronics is going to be difficult, I plan on
using an appropriately sized MOV and LM-150K (proven and reliable,
inexpensive) in front of the control circuitry.
I really can't see any substantial cost difference in either approach.
Your results may vary.
C. Smith

As far as having two power sources for an EFI airplane, my thought is that
instead of having two alternators, have two batteries-  by a new one every
year and rotate the oldest one out. I have two  Powersonic 28 amp/hr
batteries that are sealed saturated fiberglass mat, cost about $50 each. If
the alternator goes out, I have enough juice in the two batteries to fly
quite a ways to a safe landing strip. A  charged battery in good condition
is one of the most reliable power sources around.


Brian Trubee

Brian, that is how Cessna has set up their G-1000 aircraft, although
rotating batteries wasn't part of the maintenance plan. They use a split
bus, essentials on one, everything else on the other. A complete charging
system failure would still leave you with a 45 min reserve battery to power
one display at some reduced capability. I feel quite comfortable with
electronics, and a well thought out electrical system architecture. There is
a fellow named Bob Knuckolls, runs a list called Aeroelectric Connection.
His book and website cover just about any set-up you could envision, and he
answers questions with factual information backed up with well researched
documentation.

I think proper battery testing (yes, there is a right way to load test that
allows you to not have to just buy batteries on a fixed schedule) is
reliable enough and well proven, so I would be comfortable with a dual
battery, single alternator, split bus system.

When I get to the point of final board design, I'll consider a few different
back-up/emergency systems for the FI. I will share that when it happens down
the road.
C. Smith


Speaking of the 555 system this is configuration that gives
dual redundant electronics and injectors. Injectors are sized
to give max power with only two. A relay is used to change
systems like Tracy uses.

Paul Lamar


Paul,

I want to set up a flow bench to do comparative testing between a slide
throttle and a rotary barrel throttle I am machining now. The slide
throttle is wonderful but as Jerry mentioned years ago with an angled in
approach  wrapping the manifold closely over the top of the engine
becomes more challenging.  My design eliminates that problem as the
manifold comes in from the top.  Each throttle becomes an angled
manifold as well. Present device housing width with  50mm dia. ports is
about 72mm wide and 76mm in diameter.  Port tube are 2" NPS threaded
and screw into the throttle body.  For a sectional view imagine a
compass circle with north straight up. At the 270 degree location is the
center line port going into the engine.  At the approx. the 40 degree
center line is the inlet.  The inside rotating barrel has a passage way
through it.  I plan to test two versions of barrels. These are solid
cylinder with passageway milled out, and a hollow tube with inlet and
outlet holes cut out. Short shafts are pressed into the ends of the
barrel and extend through miniature sealed bearings to the outer
housing. The  shafts connect to the driving mechanism and/ or to its
neighboring throttle.

Instead of using a manometer I was thinking that using a MAF sensor would
be wiser as the info can be stored in computer program and I could test
the unit I want to use.  To create the flow I want to power up the
supercharger with an electric motor and get some data on hp. consumed
verses flow as well.

If you like I can do a side by side test with one of your slide throttles
and get some flow verses section open area  data.  This information is
valuable in identifying possible turbulence issues at partial throttle
openings.

I could use some info on the $61, ('02 5.4l V8) Rock Auto MAF sensor you
bought $61 Colin.
What size ID is it?


Doug in Japan

That is a good idea Doug. In effect you are reducing the radius of one of
the
two 90 degree bends. I am looking forward to the results from the flow bench
test. How are your Rhino skills coming? Can you do a 3D for us?

Paul Lamar
--

Doug, I'm not sure how much info on the MAF I can give you that is useable.
I have no data sheet. It has a six pin flat connector. There is no "ID" it
is a shrouded probe assembly with 3 coils, and a flat mating surface. Looks
like it could be used in a number of configurations as long as you got the
flow direction right. Haven't noodled it through yet, but I do have a
factory manual for the truck and engine. I don't know when I'll get to
digging out the pages related to it. Do you have an urgent need?
C. Smith


Paul,

Since my Windoze computer died last year I haven't had access to Rhino.
To bad, just when I was getting more proficient:)   Funny the average
life of any Windows base equipment I have ever touched can be measured
in months. Digital watches are the same with me.  Perhaps I need to ask
Uri Geller:)   Macs never a problem. Perhaps the Mac Rhino version has
the bugs worked out it by now.

Question  Michiwa has a Japanese keyboard Windows XP laptop that she
spilled cocoa on and now a few keys don't work. She is donating the
computer to the rotary engine project.  Assuming I use a   external
keyboard can I wipe the hard drive and reinstall a English operating
system on it?
If so I can be up and running with Rhino again.

Colin,  the design probe sounds similar to what I used in measuring water
flows.  If you can direct be to a picture or part number on Rock Auto I
can make a decision about using it.  I want to start testing by next
month.

 Doug in Japan

I don't know about that Doug. It does not sound good.
PC's over here are in the $200 range if your monitor still works.

There is a weekly ferry service that connects Shanghai to Osaka/Kobe.
The ferry's destination alternates each week between Osaka and Kobe.
The journey takes two days. A second class ticket on this Japan-China
International Ferry Service costs about US$180.

I know a nice hotel (Nanjing) right down on the walk street for $50 a night.
Not far from Pizzahut, Kentucky Fried Chicken and Howard Johnsons. :)

Lots of computer shopping!!

Paul Lamar

Paul,

Yes the laptop as luck would have it is a Sharp.  They don't seem to
have a US version.
Have spare keyboard, and  monitor. Please point me towards a $200
computer that will run Rhino. EEE micro is a possibility but I am
concerned that resolution suffers when plug into a large monitor.

Funny I stayed in the same hotel in Shanghai about 6 years ago.   Bet you
went to the Peace Hotel down on the Bund at night to drink coffee and
listen to jazz.   Should be a Subway across the street from where you
were sitting in the first picture.

In CA we have Frys. You buy a mother board with processor for $69
a bit of memory, a power supply, a case and a hard drive.

I am sure they are cheaper in Shanghai. Besides that you can
buy boot leg copies of Rhino and Windoze :) Don was quoting
some amazing prices for software in China.

Paul Lamar