Vac/Boost Gauge

01screw · #1 06-06-2002, 02:49 PM

I'm installing a Autometer vac/boost gauge, I tee'd into the hose going to the FMU which is giving me a vacuum reading. I actually want to see how many psi of boost the S/C is giving. How do I hook up for this? Thanks all !!

Silver X · #2 06-06-2002, 04:05 PM

Use a difference source, intake area is good.

808Hawaiian · #3 06-06-2002, 04:09 PM

If you go to a hardware store you ought to be able to find the necessary connections to make the T fitting. Look in the plumbing section. You will need to cut the vaccum hose and splice in two 3/8" fittings (for the vaccum hose) and a compression fitting for the autmoter gage tube. the three fittings will screw into a T block. If you go to the plumbing section of a Lowes or True value and take a sample of the vaccum hose and gage tubing and tell them what you are doing they should be able to help you. shouldn't cost more than 3 dollars or so.

01screw · #4 06-06-2002, 04:45 PM

808Hawaiian,
What I need to know is where to hook up to for boost reading. I've made the tee fitting.

Silver X · #5 06-06-2002, 05:17 PM

What I am saying is that you do not want to put everything on one line. There are other sources to get your boost from. Just look at the intake and you will see where all the lines go and tee off one of them. I grabbed a different line for each of my sources. You can unplug the fitting that is there and tee into it so you have to do no cutting to the factory stuff. Don't know if I explained that very well. You can do search and you'll find more info.

Even if you tee'd into the FMU, you should have gotten a +psi reading bec doesn't it activate under + boost pressures?

01screw · #6 06-06-2002, 05:27 PM

Silver X, Thanks for your info and help!! Stupid me, one end of the gauge tubing was not pushed in completely. Guess I didn't tighten the compression fitting tight enough and it slid out a bit!!

01screw · #7 06-06-2002, 10:32 PM

Well, I thought it was working. The gauge only stays between 0-25 vacuum, never show anything on the pressure (boost) side. At what RPM should it normally start showing boost.

Silver X · #8 06-06-2002, 10:45 PM

Something can't be right. Is this a 4.6 or 5.4. If 5.4 and all else fails e-mail me and I give you my number and I can direct you to the source you need. There is also Crash/Skidmarkracing that are usually on hand to help out and can call. Maybe they are out racing?

Crash! · #9 06-07-2002, 08:21 AM

If you have tapped into a vacuum source behind the throttle body, you will be able to see vacuum and boost. On the Magnacharger, tap in near the FMU. On the Procharger, tap into the factory vacuum "T" near the starter solenoid.

01screw · #10 06-07-2002, 03:08 PM

Hey THANKS to all who responded!! Went with another vacuum source and finally it works!!!!