North American Turbocoupe Organization

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On the diagram on the site. http://www.turbotbird.com/FAQpage/Vac_Diagram.htm
Where does the aqua and the green line go to when they leave the screen? I am trying to eliminate/clean up as much as I can. Also my Vac is at 16-17. Is that right? What is a good way to pin point leaks? When the car is running I know there are leaks but I cannot hear them due to loud car. And I thought Of making a attachment to a vacuum but that may be too loud also.
17-18 inches of vacuum is right on the line. I hear normal is 18-21ish. Mine makes 21.5 or so in stock configuration with a almost worn out cam.

Pressure testing the manifold will let you know about leaks. Another, quicker way is to spray WD40 on any suspect leaks while the motor is running. A prominent leak will mess with the idle.

I don't remember where those lines go. I'll look when I get home if no one responds before me. My EVTM is 100 miles away right now! :p
Note: idle vacuum may vary with setups. A performance cam lowers the vacuum, as well as engine timing.

I think exhaust mods (downpipes, etc.) might as well. Not real sure though!!
The green line goes to the speed control amplifier in the inner fender on the driver's side. Not sure on the aqua line unless if is related to an auto trans car. That is only a guess. 16-17" is a little low if the gage is accurate. 18-21" is normal. There are lots of past posts on finding vacuum leaks. Search on that term and my screen name to narrow the range.

Also check your email
As far as I know the guage is accurate. But it did say that there is a inaccuracy 1psi per so much altitude. I am at 4500ft. My timing is at 14deg. Will that add or subtract vacuum? I will try the WD-40. And do another search.


Pete I can't check my email. It is at work and I am on leave due to baby. Can you forward to my [email protected]? Thanks
Found a great post for it. It mentions that you (Pete) were going to make it a Tech article. Why is it not? I may be able to type it up and give credit where it is due if you need me too. Here it is.

http://natomessageboard.com/cgi-bin/ulti...1;t=013692

Although I have no compressor I am going to get the parts anyway and try it with a bike tire pump first. If that dont work I will drive to the free air spot.

I plan to hook it to the turbo. I will get measurments for vam and turbo.
Thanks Pete.
I resent the email. It's pretty much the article you linked above, with pictures.

A bike pump won't do it. You also must regulate the air pressure down to around 10-15 psi, no more. Connect it to the compressor inlet, Don't run it through the vam.
So Could I just go to a free air place and use their compressor if I rig it right?
Not sure that one of those tire filling pumps is going to be big enough. I have a 2 stage with a 50-60 gal tank and an adjustable regulated output.

You could get by with less but you probably need something with a tank. Just a pump may not work
Remember there is a lot of volume to fill and some things are going to leak no matter what. Throttle bodies always leak some, usually EGRs leak some (it's a matter of how much??) A small pump only setup may never be able to build any pressure,
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