pinging - weber carb

[sdsurf]

I got my engine all dialed in timing wise and it runs great. But, when I punch it in say 2nd or 3rd to open the secondaries it pings pretty loud. I am running 89 octane.

 

Thoughts?

[datzenmike]

Dial the timing back till it stops and run it there. Or you maybe able to run the secondary slightly richer. This may cool the cylinder charge enough to get rid of the pinging. Then advance the ignition up just under the pinging. This won't affect mileage.... well not untill into the secondery. Can't remember everyone's car. What you got and done to it?

[sdsurf]

Dial the timing back till it stops and run it there. Or you maybe able to run the secondary slightly richer. This may cool the cylinder charge enough to get rid of the pinging. Then advance the ignition up just under the pinging. This won't affect mileage.... well not untill into the secondery. Can't remember everyone's car. What you got and done to it?

 

521 with an L20b (stock) and weber carb

[MAG58]

Which weber carb? There may not be a secondary.

[sdsurf]

which weber carb? There may not be a secondary.

 

dgev

[kiznook]

2nd what Mike said. Also maybe try 91 octane

[MAG58]

agreed. Back off the timing to see what you can run without pinging. Going a little richer will help the situation, but too rich and you'll get hesitation when you transisition onto the secondary.