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I have a 1976 Nova I am restoring, and Im trying to keep the original 250 I6 motor and everything for now. We got it running, but the carb is just awful. There are barely any of the vacuum lines hooked up, most were just blocked off. It will run, but you can tell its having alot of carb problems. And if you slap the gas quick, it will make a sound like its sucking mass amounts or air, and it almost stops for a second then comes back and revs. I need the layout for these lines. If you could show me a picture that would be amazing, but I'll take what I can get. Thank you.
 

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You should have vacuum diagram sticker on the core support. If not then the shop manual will have the vacuum hose routing. Generally, people blame the carburetor when there may be other things contributing to poor running. It may be a matter of diagnosing and fixing multiple problems
 

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67 4 door, 65 wagon (in pieces)
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This paragraph applies to an instantaneous bog, hesitation, or stumble upon acceleration. Constant hesitation is covered under “surging”. This paragraph also applies to relatively stock engines with the original carburetor. We will discuss two types of bog: the first is bog when the vehicle is accelerated from a stop; the second is bog when the vehicle is accelerated from cruise. Bog from a stop is virtually always (and generally erroneously) diagnosed as a faulty accelerator pump (see the section on “accelerator pumps” for testing). Most modern carburetors are designed to function with roughly 0.020 (20 thousanths) clearance between the center of the throttle plate edge, and the throttle body at a point equidistant from the throttle shaft bearing areas. This clearance allows for maximum velocity of idle air past the idle ports. Exceptions to this are GM carburetors with the idle speed air screw, and end carburetors on tripower. Setting the idle for the highest vacuum idle reading will result in too little clearance of the throttle plate; forcing too much of the idle mixture through the lower idle port and too little through the idle transfer slot. This will cause a phenomena called “puddling” where little droplets of gasoline adhere to the intake manifold runners. When the throttle is opened, there is now sufficient velocity of air to sweep all these droplets into the cylinders, creating a mixture which is too rich to burn, hence the bog. As soon as the overrich mixture is pumped out the tailpipe, and a normal mixture is ingested by the cylinders, the bog disappears. A defective advance mechanism can also cause bog; as can a defective accelerator pump. If bog exists only from an idle, not when accelerating from a constant speed, the idle adjustment is probably the culprit.

http://www.thecarburetorshop.com/Troubleshooting.htm#Acceleratorpumps
 

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if it's a 1 barrell rochester, you can almost guarantee that the accelerator pump isn't working properly. Get a rebuild kit, clean the carb super-well, paying particular attention to the internal passages.

The vacuum lines may not be a problem at all, it definitely sounds like an accel. pump problem.
 

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^^^^x2 The rochester 1 bbl's are crap! Swap heads with an earlier non-integral inline six, intake manifolds and add a Holley 390cfm 4 barrel! :yes:
 
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