<VV> Spyder Tach and XR700 ignition

[N2VZD TIM]

I would not touch that Tach adjustment unless you have a test setup.  I finally  made a simple  one for when I am working on dash instruments.

Sent from AOL DesktopIn a message dated 6/1/2022 8:05:35 PM Eastern Standard Time, virtualvairs at corvair.org writes: 
As far as I know, that's a setting on the tach, not the ignition output.  Basically the trigger wire indicates each spark, and the tach converts that into RPM.  Since we are dealing with a stock tach, that shouldn't be the case here.

I don't know enough about how a tach works to diagnose it further, unfortunately, other than to suggest re-checking the connections.