Posted for "Matt Hapgood" <hapgoodm94@alum.darden.edu>:

I have a home-brew automotive type FADEC in my plane.  I am using a product
made by Electromotive, and I have adapted to the airplane.  Dual battery,
dual systems...

In general, Yes, it starts and operates just like a car.  I do not have a
mixture control, but I do still have a prop control.

It will start in sub-freezing temperatures (I've only tested it down to
about 25 F) without any problems.  There is no idle problem - it will easily
idle at about 650 RPM.  It will throttle right after the start, although at
this point I am probably running it a bit rich for the first 20 seconds
(part of the starting mixture program).

As for the "not so great" issues:  battery voltage is a problem.  I don't if
my problem is related to my starter, my wiring, or my batteries, but it will
barely turn over when it is cold.  Even when warm out it is still sluggish
turning over.  I have two 17 AH batteries mounted behind the seats, and 4 GA
cables running to the starter.   28 Volts would probably solve that problem,
but would introduce many other potential problems...

Matt