In article , Ray Toews wrote:

I am removing the vac T&B and putting in an electric and thinking of
removing the regulator and then apply full venturi vacumn to the
horizon. Is it possible to over rev a gyro with an outside venturi?
I am doing this because even after a 15 min runup I am several miles
off the runway before the horizon stabilizes, not that great on a nite
takeoff.

Ray

Vacuum gyros are meant to operate at a specified vacuum level, in order
to maintain their proper RPM. Applying extra vacuum would cause them to
spin too fast and cause premature wear on the bearings.

This is one of many reasons for vacuum pumps, instead of venturis.