vacuum gauge

Hi probably a stipid question bit I want to fit a vacuum gauge to my 3.9 efi v8 . Would I connect it to the pipe from dizzy to plenum chamber . Or would this affect the dizzy .

you can t it in there..it should make no difference..

My vacume gauge is connected directly to the small pipe at the very back of the plenum cover. The ignition advance vacume take off is before the butterfly and I doubt you'll see enough vacume here for the gauge to work. Most vacume gauges run 0 to -1 bar mine from the plenum sits around -0.6 bar at idle.

are you sure??there is no vac before the butterfly..(very little)

This is what I thought, but that little pipe above the throttle butterfly seems to be on the air filter side of things, and when I tried is definitely has less vacuum than the pipe at the rear of the plenum. My vacuum gauge would barely register on that throttle inlet pipe, unless of course I have issues and that pipe is somehow blocked?