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Good Response, Bill.
Whether EFI or Carb, the fuel system is one of the two crucial
systems in an aircraft - the other being ignition. If either is not done
carefully and attention to detail and good workmanship, problems will come -
sooner or later, but, they will come.
The EFI system produced by Tracy with its redundancy, many
tuning modes, etc, is one I feel very comfortable flying. Having had an
after-market EFI fail completely (fortunately) on the ground, the comfort of
redundancy with the RWS EC2 and its well thought out design has made the last 8
of my 10 years of rotary flight a pleasure.
My personal perspective is that EFI simply gives me
more insight and control over the engine's fuel parameters (note - that is not
always a good thing as it gives more opportunity to screw things up also)
than a carburetor. Having said that, once you get a carb tuned in then you
can pretty much forget it.
But, the very design features that permit the EC2 to be twixed
and tuned to achieve the optimum fuel feed conditions are also those that can
frustrate some. It is clear that some folks do not take the
time to read (or perhaps having read it just don't understand some
aspects) Tracy's instructions - if you intend to vary from them then you better
know as much (or more) than Tracy about EFI design and tuning.
If you don't understand some aspect of the instructions
- ask Tracy or even post it to this list - who knows, somebody may know
{:>). If you deviate from Tracy's instructions - then you have designed
a new system with unknown (until tested) features {:>)
Either approach (carb or EFI) will fly the rotary just
fine. There are (as with most everything) some pros and cons to each and
some folks simply feel more comfortable with one than the other. Hey,
that what this is all about - you get to do it you way. Just do it with
knowledge, experience (if you don't have any find someone who does) and eye to
examining each component/connection with the attitude of if this should fail -
what happens? If you don't like what happens, then take the time, get the
knowledge to minimize the probably of that component failing or the consequence
of failure.
Well, back to my coffee
Ed
Kevin, not heresy at all. There are several factors here.
First Tracy is doing some development work, but offering a very inexpensive
EMS. Once you get everything right it should give great service. Ed Anderson
is a good indicator that the system will run for a long time once dialed in.
Some guys are doing fully redundant alternators AND batteries and not just
because of the engine, rather a fully electrical panel. Go with what you feel
secure with, and fly accordingly. I have posted before that mags can have
trouble with high RPM engines. So unless you have an early front cover and are
willing to run POINTS, you will still need an ignition.
Most of the carb inquiries have been on account of
George and Richard going with single rotors. I believe Richard may have a
modified stocker ignition and a carbed P-port. He has done us all a great
service building, and now testing a hybrid end plate. mostly aluminum, with a
steel insert. (GOOD LUCK RICHARD!) Lynn and I have both grafted old
mopar EI ignitions on to other engines. These require battery power but are
otherwise unkillable. Available for next to nothing from J.C. Whitney but you
must do the set up and wiring yourself.
Tracy's system looks to be a good one, but you must realize
that wiring and plumbing ABSOLUTELY MUST BE DONE PROPERLY. This is equally
true of a Lycoming install, but more of the FWF or FWB (Canard) is available
to you off the shelf. We lost Buly to some mistakes that he made with the
wiring, not a complete failure, but intermittently causing him fail to
start problems out of the blue. Buly is a good builder too and the
troubles drove him and Tracy crazy. Only when he finally pulled his control
box for an update could Tracy find the problem. He is putting in a Lyc.
clone. This is a terrible loss for us. The problem was self generated, (he
re-soldered a connector to gain clearance rather than re-do the panel), and
that connector had the classically difficult to diagnose intermittent problem.
Bully and family made the tough decision to forgo any further pioneering. To
bad too, his plane would have been a great addition to the conversion
"fleet." The point here is, like flying a cross-country, plan the
install and then stick to the plan. If you run into a bind do the needed
rework and don't "make do."
You can go with carbs or EFI, there are several,
Tracy's is aviation redundant, and the cheapest though. You must be able to
understand the needs of digital electronics to install ANY EFI or EMS.
Troubleshooting wiring is always the toughest job!
This is a super long post already but I must tell you
about a failure I had back in the days I did mechanics work to pay for school.
I was doing a tune-up on a Kawasaki 175 single. Mag ignition 2 cycle, came in
running for a regular service. I did points, timing, plug, carb adjustment,
the works... After finishing my labors, THE DAMM BIKE WOULDN'T START! I
checked spark with a test plug on the cylinder head and drained the float bowl
to check fuel it was clean. This is the simplest engine in the world, a 2
stroke single! To cut to the chase the brand new SPARK PLUG was bad. I broke
it apart later to check and found someone on the production line had left out
the copper core connecting the top of the plug to the center electrode. The
point is no matter how simple you think a job is it still requires logic and
perseverance to be SURE everything is correct. And even "simple" stuff can
fail.
Bill Jepson
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