My tach says I need to connect it to a particular place, as a source for RPM readout.
-Tach sensor port?
- vacuum system?
- charging system?
What is "4-mil" wire btw.

Is it short for 4mm or "4-MIL (spec)?
(MIL spec is US military specification, i think)
I'd love to find out where my EA82 is idling at,
as if varies depending on engine temperature,
and I'd also like to see what RPM it detonates at on 91 and 95 octane fuel.
I think with my current state of tune, 98 octane may be overkill,
as I suspect it's slower now before 4500rpm.