So ... after a crazy week at work got a bit of shop time this weekend to finish up the Controller for the e-pressure setup that maps the ignition speed. I lack Dave's electronic skills so this is a bit of a triumph for me
.
the controller is a simple Arduino mini with a PCB shield with the motor control Mosfet and a Optocoupler to allow for different Ignition and board voltages. Its powered by a single plug into the receiver that also brings in a spare channel for a prime function - This connection also powers the pump which runs on 5-6 volts and only draws about 100-150ma. another servo plug gets connected to the ignition tach output to sense the speed of the engine - The program has an expo function that curves the output to mimic exhaust pressure. Its adjustable as in the "predicted" max speed at which the pump output speed will be max.
Below is a demo of the system and a "live fire" run with a very quick 2 minute tune. My "jet size" is too big again - the opposite issue I was fighting before when had to restrict the exhaust to get enough pressure to help fuel feed - I have a 11mm proper (very fine) thread tap and die set now and will probably work on a less restrictive exhaust system now to allow better breathing.
The system works well up to 1.5 psi but I could only run 0.6 or I was too rich. as a test I switched from a 18-6 APC to a classic 16-8 MA and picked up about 7-800 rpm and it didn't need a mixture reset. I tried the leaf blower trick and could only get a few hundred RPM more but it seemed to handle it well... Now we have to "air test" it but I'm afraid our flying season is quickly ending up here.. It was cold today and trying to snow...
Dave has the "code" now and i'm thinking he might be able to cook up some better code and hardware.. and maybe integrate it into the mixture board.
https://www.youtube.com/watch?v=e_1L...ature=youtu.be
https://www.youtube.com/watch?v=vXyz...ature=youtu.be