Brent,

 

Nice.  Here is what I liked about ignition systems I have used:

 

1. Magnetos:

Uh, I couldn't think of any....

 

2. LASAR:

Wiring from magneto body was thru an 8" pigtail with high quality connectors used in the harness.  This eliminates any problems from vibration in connectors hard mounted to the device(s) on the engine.

 

3. Plasma III dual system:

a. interconnected electronics so that if one system failed, the other would compensate for the timing difference when operating on only one plug.

b. Display of fundamental parameters (timing delivered by each half, RPM, MAP) so that anomalies may be noted.

c. Robust crank position sensor.

d. Ability to use large gap Iridium plugs.

e. Longer, high energy spark to greater ensure the start of every combustion event.

f. The ability to affect the timing based on the Compression Ratio.

 

4. P-Mags

Uh, haven't used those yet.

 

Of course, it would be even more interesting to address those engines that are supercharged or turbocharged, not to mention the induction system limitations inherent carbureted engines.

 

Scott Krueger

Getting a lot from the little engine that could.

 

 

A while ago I was approached by Monty Barrett of BPA to develop and
ignition system for the 9 cylinder M14 radial engine. The magnetos for
these engines were out of production and unreliable. We applied our
experience designing certified aerospace electronics and came up with a
magneto replacement system with a Timing Controller that featured an
internal poly-phase alternator, manifold pressure sensor, independent
High-Q magnetic flux sensors and dual microprocessors with cascading
redundancy. Everything is packaged in a billet machined, O-ring sealed
MIL-Spec, water and dust proof anodized housing. The Timing Controller
is coupled to independent "Coil Near Plug" high energy Smart Coils that
deliver a measured 80+mJ of energy to the spark plasma. The entire
system is rated to 125 degrees C operating temperature (257 degF), 10G

sign-on-random vibration, direct and indirect lightning effects as well
as a host of other DO160F test requirements.

While we were designing this system it occurred to me that I would like
a couple of these on my IV-P, so we designed it so it could accommodate
6 or 9 cylinder engines. The only difference being the internal sensor
ratio and firmware.

The system components have passed qualification testing and the 9
cylinder system is currently on the BPA dynamometer undergoing
performance mapping and endurance testing. This is where we develop the
advance parameters for RPM and manifold pressure. It really isn't
practical to attempt to develop these advance curves without a dynamometer.

Monty at BPA is currently booking orders for the 9 cylinder M14 system.
The problem with the 6 cylinder "market" is that there are many
variables and each significant variant of manufacturer, induction system
and compression ratio needs to be dynomometer qualified. So, to solve
this problem Monty will be offering a significant discount on the
ignition system to select 6 cylinder customers who have BPA perform
their overhaul and consent to having Monty performance map their engine
after the post overhaul dyanamometer run-in.

The reason for the dyno testing is that it is not a good idea to just
make a guess at the correct timing based on RPM and manifold pressure
and then go fly. That would be like buying a suit out of a catalog. A
good outcome is unlikely.

The attached picture shows the Timing Controller. It replaces the
magneto and contains the poly phase alternator, electronics and manifold
pressure sensor. The MIL-Spec connector is the interface to the
individual coils. The red cap covers the -4 JIC threaded fitting for the
manifold pressure connection. Under the blue cap are the firmware update
connector and integral static timing light. There is NO separate "Brain
Box" to deal with.

The system is not available for 4 cylinder engines at this time.

If you are interested, contact BPA http://www.bpaengines.com

Regards
Brent Regan



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