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  1. #1

    Default 79' Chevy Scotsdale 350

    I have a 79' chevy 1/2 ton 4x4 pick-up, I replaced many parts and upgraded parts like , carb,headers,intake,etc......My problem is ,I hear a spark knock at high speeds or climbing hills. How do i eliminate this noise. Is there something i overlooked in my upgrades, or is it just fine tuning the timing or ajusting the carb??????? I need help??????

  2. #2

    Default RE: 79

    How loud is the noise?

  3. #3

    Default 79' 350 chevy

    the noise sounds like a bad gas sound , not very loud but very annoying,, i have headman headers and glass packs with staight pipes to get an idea, and i can hear it from inside the cab,,,,,,,

  4. #4

    Default RE: 79

    Is it an original 350 from 79 in your Scotsdale? If so, how many miles, etc?
    Some people call me the space cowboy ... some people don't.

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  5. #5
    Sr. Engineer Aeropagus's Avatar
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    Default RE: 79

    Are you hearing the knock mostly under load? I agree, more information on the age/condition of your engine will give some clues.
    John ~ New Mexico ~ It's all about the bowtie!
    2007 GMC Envoy & 2010 GMC Sierra

  6. #6


    You can back the timing off a little or try running a higher grade of gas. Either should help, but the gas is the easiest to start with.

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  7. #7


    Yes, it's always best to start simple. Keep the tank full, try a different brand with different additives and higher octane, etc.

  8. #8


    any news?

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