I have '84 Jimmmy and just had a 5.7L with an '86 & later block and '85 & earlier heads. It is bored .040 over, as far as I know a stock cam. I used a stock intake and it has a edelbrock performer 600cfm carb in top. The intake that I used used to have an egr valve and I removed it and made a plate to cover it. This truck has no emissions on it.

I have the timing set right now at 2 degrees BTDC and RPM is at about 650. It starts and shuts off fine. When driving it, it still has a ping to it while accelerating. I have went as far as putting the timing at 8 BTDC to try to get rid of the ping, but its still there. Also checked all vacuum lines and all is good there.

If anyone has some insight on this problem, please let my know. I am all ears on this one!

 

It sounds like there is a problem with the advance in the distributor. Have you taken it apart and checked the condition of the vacuum advance as well as the mechanical advance?

 

I have checked the advance system in the distributor. it is an aftermarket from Jeg's, I purchased it about 3 yrs. ago. I have thought about buying the advance rebuild kit from Jeg's, but was wanting to get some input before buying it. Actually, just bought the kit from Jegs. I will let you know how it goes. thanks for replying.