In article ,
wrote:
From what I understand, the digital tach is a very simple install.
It only needs power, ground, and P-leads from the ignition switch. Of
course it requires a 337 paperwork bu11$h!t, but since it's STC'd, even
that's not a big deal. My tach is about 100 RPM low (checked it myself
with a strobe tach), so I just take that into account when cruising. A
friend of mine told me once after I flew a cross-country flight and
guessed the fuel burn that I'm the only guy he knew who would be able to
tell the tach was off 100 RPM by the fuel required after the flight. It's
dead-on at 8.5 gal/hour on 180hp @ 65% (with tach correction factor).

I think the fact that the digital was digital is what scared him off.
He wasn't very comfortable with electronics.

I don't worry about it too much because, as you noted, I know that it's
low and take that into consideration.


JKG