Installing Vacuum Guage.. Having Trouble

[crossfire]

I just recently bought a 3 gauge pillar pod and started installing my gauges.. I started to install the vacuum guage and I just can't find a good spot to tap into.. Do you guys have any suggestions?


I have a 5.7 V8 Charger

[richierevs]

I just recently bought a 3 gauge pillar pod and started installing my gauges.. I started to install the vacuum guage and I just can't find a good spot to tap into.. Do you guys have any suggestions?


I have a 5.7 V8 Charger

There aren't any real good/obvious places to tap into for vacuum, and the main vacuum is sourced from the front rather than the back of the intake manifold.

What type of gauge do you have? Is it a pneumatic gauge (draws directly off a vacuum source) or does it have a electrical sending unit?

[Popeye's Hemi]

You could try the vacuum line that is on the back of the intake manifold that runs to the brake booster.
It's about a 3/8" ID hose.

[richierevs]

You could try the vacuum line that is on the back of the intake manifold that runs to the brake booster.
It's about a 3/8" ID hose.

If you have an electronic sending unit for the vacuum, which usually has a 1/8 NPT fitting for the sending unit and 3/8" OD for the vacuum line, you can tap into the vacuum line for the brake booster without worry. Here's a link:

http://www.jegs.com/p/Mr-Gasket/Mr-G...46566/10002/-1

If the sending unit ever fails the vacuum remains intact.

If you have a pneumatic gauge, however, and there's a failure with the feed line to the gauge (i.e., the feed line is cut or disconnects), there's a chance that you'll loose partial vacuum to the brake booster and the engine will rev higher at idle due to the vacuum leak.

**Edit**

The vacuum sending unit should be installed upstream from the vacuum check valve to get an accurate real-time reading of vacuum. Most often the check valve is mount directly on the brake boost. I mention this just in case the check valve has a different location.