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Discussion Starter · #1 ·
First things first:
The Car:

- 1967 GTA K-code coupe with 98667 miles.
- 289 HiPo bored .030", esentially stock; c4 automatic
- Carb specifics: 600cfm Holley 4150 with mechanical secondaries and mechanical choke.


The problem:

- She will start up and idle perfectly, she sounds incredible. My problem comes when I put it in gear, she dies instantly.
I don't have a vacuum advance distributer and my PCV valve connects to my carb spacer so we just plugged off the vacuum ports on the carb like the manual says. We tried connecting the ports to vacuum and it only made her run worse at idle in nuetral.
No amount of adjusting the idle up or messing with the fuel metering will keep her from dieing the instant she goes into gear. She's also very prone to flooding once she does die, as in, she'll usually flood after the second or third time she's cranked after dieing.
We're at a complete loss as to wtf is the problem.

Any ideas?
 

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Will the engine rev up while in neutral?
Can you disconnect the mechanical secondaries and see if it does better?
How is the accelerator pump? Will it squirt?
Are the needle seats stuck open?
Is the power valve blown?
Has the carb every worked OK on this car or any other?
A few things to check.
Good luck,
Rick
 

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Has the car ran OK with this carb or was it just installed?

Is the carb new? If not, has it been rebuilt correctly?

Do you know how to set the carburetor idle speed/mixture correctly?

Have you "read the plugs"?


Did you put the carburetor on because the engine "didnt run right with the old carb"?


Do you know for an absolute fact the ignition and engine are in good shape?

Can you/did you try a known good carburetor?

Is the gas in the tank more than 9 months old?

Is there a fuel filter before the carburetor?
 

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Like someone suggested, check the power valve. These Holleys are known go chit the bed after 1 backfire.
 

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Discussion Starter · #5 ·
This is a new carb that was bought to replace the original that just wasn't running right.

The plugs had a lot of carbon fouling.

I doubt the powervalve is blown since it is a brand new carb that has never backfired.

The ignition and and engine are in great shape.

The fuel tank is brand new as well as the sender and filter (installed the same day). The fuel is also brand new.

I know how to set the idle and mixture.

The engine runs perfectly fine in neutral. It will rev up in neutral.
 

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floods? maybe the neeldes got clogged with some debris with all the new stuff you put in. if all else fails, try to get a carb that you know is working and try that... good luck
 

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Does the problem occur when the engine is cold? hot? both? What kind of choke system does it have?

Does the engine die exactly when you put it into gear, or is it during the transition away from idle? Couple of things to check - fuel pressure, float level, and accelerator pump discharge.

Have you put a vacuum guage on the engine?

When the engine dies, can you see gas dribbling out into the bottom of the manifold, without activating the accelerator pumps? That's a telltale sign the power valve is blown - but, you said this carburetor is new - did the engine ever backfire, and if so, did it run okay before the backfire?

just a few more things to look at...
 

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Well, hmmm. Does the c-4 have a neutral saftey switch?

You said your using a 4150....weren't they used on big block 428CJ's? That's 735 cfm and if I'm correct the 289's used a much smaller carb. Not that I think that's the prob, just an observation.
 

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Discussion Starter · #9 ·
Well, hmmm. Does the c-4 have a neutral saftey switch?

You said your using a 4150....weren't they used on big block 428CJ's? That's 735 cfm and if I'm correct the 289's used a much smaller carb. Not that I think that's the prob, just an observation.
No neutral safety switch.
4150 is just the model, the carb is a 600cfm 4150.
 
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