I am also thinking of mounting
 one of the cheap $80 12 bit AD to D data acq system back there
 with the USB interface to monitor the 555 EFI system and its
 sensors on a notebook computer. Add a few ten dollar pressure
 sensors and lots of things are possible. The A to D can also handle
 the fuel flow read out and fuel totalizer in software.

 http://www.hytekautomation.com/

 I just came up with another idea using a tiny electronic load cell
 out of a cheap bathroom scale incorporated into the motor mount to
 measure prop torque. Knowing prop torque and prop RPM you know HP
 out of the gear box. The A to D system can measure that as well.
 I got the idea by watching the TV program Deconstructed on the Science
 Channel. I'll appropriate  Robin's  bathroomscale :)

 -----------------------------------------------


 Here are some pictures of the load cell in Robin's bathroom scale :)
 I'll have to buy her a new one at $34.

 It is battery powered for the life of the scale in that black container
 behind the LCD read out.

 I'll work on a 3D dwg for the mechanism for the end of the S-beam
 motor mount. One side has all the load due to engine torque.
 The 12 bit A to D has such  a high res and a wide dynamic range
 it does not matter if it is measuring the weight of the engine only
 when the engine is not running. The trick is have it bottom out
mechanically
 so it does not damage the load cell during hard landings and high G pull
up loads.
 That would be like having an over 300 pound person standing on the scale.

 Paul Lamar

Hi Paul,

Those things like to turn themselves off after a few seconds.  The ones
I have make you tap the scale, then it goes through several seconds of
a power up sequence.  You may have to figure out some way to bypass the
automatic power feature and supply a larger battery.

Bob W.
--
N93BD - Rotary Powered BD-4 - http://www.bob-white.com
3.8 Hours Total Time and holding
Cables for your rotary installation - http://roblinstores.com/

I figure I could use just the load cell part.
It is probably The crystal type.
The force is applied to a piezoelectric crystal
and you measures the voltage across the crystal.

Paul Lamar


Paul,
give you a new toy and you just keep finding great new ideas on how to use
it.
:)
Larry