VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1929-1932 1931 Chev pinging

I have been using the Champion D16 spark plugs for some time. Around town 30-35 mph it works fine. I have the engine timed according to the "revised specs" provided by the VCCA web site. At 45-50 mph, the car begins to ping and I have to pull the retard knob to reduce this noise. Would changing the plugs to a colder plug help reduce this pinging?
If so which plug should I consider using.

The timing specs. that you refer too are only for the AC-C86 and AC-C87 plugs, not for the Champion plugs that you are using. Change to either the AC-C86 or AC-C87 plugs and see if that makes a difference. The plugs should be gapped at .040" and the timing should be set at 18 degrees with those plugs.

I tried to look for the AC Delco c86 plug. The cross references are the following:

Autolite Copper Core 386

Champion Copper plus D14 or box #514

Motorcraft BTS-8

The AC-C86 plugs are discontinued but new old stock plugs are available from some parts suppliers. Anyway, the replacement plug for the AC-C86 is the AC-C87 and you can get those from your local NAPA store. They will either have them in stock, or if not, they can order them since the AC-C87 plugs are still available.

JYD, quick question. With the AC-C87 plugs, is the gap still .40 and the timing 18btc? I am going to a complete tune up as part of completing my 31's restoration. If I can't find the C86's I figured I'd ask now about the C87's.

From my post above on March 28th:

Sorry, missed that post.

Ya just gotta learn to pay better attention.