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1967 ford mustang 289, 4bbl engine has been rebuilt/ w performance camshaft. will not idle correctly . carb has been changed , ignition has been updated , wires cap points and rotor ? checked for vacuum leaks ? idle vacuum is 13 to 14 in ?

Posted by kenb469 on

  • brbclayton10 Oct 02, 2008

    I am having the same problem. I just changed the intake and carburetor from a 2bbl to a 4 bbl. The intake now is a performer series and the carburetor is a 600cfm Edelbrock with a manual choke. Before the change the car idled and performed fine, but now I just can't seem to get it to idle correctly. The best I have tuned it, when stopping and starting at a stop sign, the engine would hesitate if I would barely push on the gas pedal. But after that it would run hard. What should I do?



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Hesitating when from a standing start, then running well can be caused by having too big a jet size. I dropped the size of the jets on my Holley 4V, and it solved that part of the problem. The accelerator pump will push in too much gas, momentarily "drowning"the engine til you get enuff air to mix with the gas.

Posted on Apr 21, 2009


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1967 ford mustang coil is getting so hot it turns of could this be from my points not gauged right? Plus at idle it sounds rough where do I start?? Help please

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Iam a 1960's guy, but don't remember the exact voltage
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at least back in the day

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I have a 1966 mustang 6 cylinder and when I am driving it will sometimes stall we rebuilt the carb and looked at the choke it was loose and not tight that seamed to work for a little but it seams when i...

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What are duel points on a 351 ford motor?

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I have a newly rebuilt engine (289, 4bl) with a Demon carburetor (Road Demon Jr. / 525 cfm). The engine idles, and at strong acceleration runs fine. When I try to moderately accelerate or try to maintain...

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