Do you have a manual? I get the same pinging sound once in a while. I switched from an H-pipe to an X-pipe. Made no difference with the pinging. If it is not your timing, it could very well be the grade of fuel you are using. Are you using 87 or 93? Gradually change the grade of fuel and see if there is an improvement. Whats your compression?
350 SB, Holley 770, Air Gap, HEI
M-22 Special Wide Ratio 4-Speed
3.73 Posi Rear, Hotchkis Suspension
Naked Lady Shift Knob
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