I tapped mine in just before it hooks up to the stock Vortech FMU. Is it preferable to have it at the T where all of the hoses come together? Reason I'm asking is that I'm still getting 15 Hg vacuum despite tightening up all of the connections.

 

It shouldn't matter where you tap in as long as you're tapping into a line that has its source at the nipple after the throttle body (in between the TB and IACV). The fpr vacuum line comes from that, so if you tee off the fpr line you're good. There is another vacuum source that comes out of the bottom of the TB. That leads to the egr control valve solenoid. Don't tap in there because you will get low vacuum when the throttle plate is closed. Maybe that's your problem?

 

I tapped into the hose that runs into the top of the FMU. Is that the problem?

I get like 10 ~15 Hg as soon as I turn on the engine in the morning.

 

And where is the fmu hose tapped into?

A low vacuum is normal when the engine is cold and the idle speed is high. Once the engine warms up and idle speed drops to 650-750 rpm, the vacuum should be around 18-20 in Hg.

 

A good healthy engine should see 19-20HGs. My new engine sees 20HGs all the time. I tapped from the vacuum line that connects to the top of the vortech FMU. Very simple