Found a used Holley TBI - Missing a vacuum port for MAP - what do I do?

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Mattchu60

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Hi All,

I found a nice used Holley TBI (the 670 cfm one). Thinking about getting it, but I have noticed that the vacuum port on the TBI for the MAP sensor (its the port on the rear of the TBI) is missing! The "hole" is there, but the stem is gone...I have no idea how, but it must have been pulled out.

ANy clue on options for this? Is this fixable? Or should I just pass it by?
 

MrMarty51

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Maby could find a piece of steel fuel line and J-B weld it in, if it is`nt tight enough.
If the hole is big enough, it might could be tapped to 1/8th inch pipe and a slip on hose adapter threaded into it.
Plug it shut and come off the intake manifold with a hose to direct vacuum, that is what that, used to be fitting, used todo.
 

89Suburban

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:popcorn:
 

Jims86

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Best thing is call Holley, they may send you one to press in for free.
Or you could plug it, and run it from Manifold vacuum.
 

MrMarty51

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Hey 89, You got another bag of that ??? :popcorn: Why thank You, Here`s a beer to warsh that stuff down with. :favorites13: Mines juz a root beer though, because, when I drink I have no friends. :happy175:
 

X-cabsquarebody

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On my Holley Porjection TBI 2D system it did not use MAP sensor , and did n't have a port for. The system comes with it's own computer, and wiring. Holley used a GM style throttle body, and TPS. Oh, it didn't have a idle air valve either. Is the hole were the port should be drilled all the way through?
 

Mattchu60

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You must have the entire projection system then? This is just for the TBI only, no additional stuff, although I think it is the same size/model of TBI that comes in the total system.
 

X-cabsquarebody

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Yes, I had the whole system on a CJ7 Jeep. And the throttle body in the kit is 670 cfm. It would be hard to tell the difference between the Holley replacement TB, and the Holley Projection TB at a quick glance. The projection TB also has an adjustable fuel regular. Hope I'm helping?
 

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You must have the entire projection system then? This is just for the TBI only, no additional stuff, although I think it is the same size/model of TBI that comes in the total system.

Yup they are the same. the one you have is the direct replacement unit.
 

89Suburban

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Hey 89, You got another bag of that ??? :popcorn: Why thank You, Here`s a beer to warsh that stuff down with. :favorites13: Mines juz a root beer though, because, when I drink I have no friends. :happy175:

Why thank ya. :cheers:

I have the same problem drinking beer. I start out with 12 friends and one by one they start disappear.... :D
 

MrMarty51

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Why thank ya. :cheers:

I have the same problem drinking beer. I start out with 12 friends and one by one they start disappear.... :D

:lol::roflbow::happy175: Him, " Whiskey for Me and My friends", Me, "Whaddya mean, I drink whiskey and I have NO friends ".:happy175::happy175::happy175:
 

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