[racefann82003]

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??????

 

[ChevyFan]

RE: 79

How loud is the noise?

 

[racefann82003]

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,,,,,,,

 

[ProzacKid]

RE: 79

Is it an original 350 from 79 in your Scotsdale? If so, how many miles, etc?

 

[Aeropagus]

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.

 

[GaryL]

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.

 

[ChevyFan]

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

 

[ChevyFan]

any news?