Guys -- here is more info I found online. This is what a guy posted. 1) His comment Pinging is caused by: Too high of a temperature in the cylinder. At about 2500 deg F. ping occours. The hotter, the more ping. ** This also creates a lot of NOx, which is what the EGR is designed to control. Many of our cars do not have or never had EGR valves. ** The heat range of the spark plugs makes a big difference. Too hot of a plug can cause severe ping to the point of engine damage. All spark plugs have various heat ranges. They all also have different internal resistance. The hear range will be by vehicle application, but the resistance is not. 2) My next step to try to resolve - I will pull my plugs and try a different range than what is in there and see what happens
First things with plugs, make sure they don't have any aluminum globbed on them. It may be detonating for a variety of possible reasons.
Did you ever try sea foam or any type of top engine cleaner ? Carbon build up is probably the worse offender.
In most cases the stock, factory OEM plugs will be correct plug and heat range. High performance and modified engines need a cooler plug. You might need a slightly cooler plug if you have a hotter ignition.
In an earlier post I suggested sea foam I wondered if he tried it. I had a daily driver that would start to ping about every 10,000 miles a can of top engine cleaner and it was good for another 10,000. I look for the cheapest-easiest fix first.
Exactly, there are lots of reasons an engine will ping, or should I say a lot of things will cause an engine to ping. Carbon, timing, lean condition will all cause it.
Not many cars here have an operating EGR valve on here and most likely run correctly, aka no combustion ping. You have a 305? Look up the correct OEM plugs for it, check against what is in the engine now. First thoughts always are incorrect timing, too-low octane and hot spots in the combustion chamber. We used to knock the carbon loose by running a trickle of water down the carb while its running. Any modifications made to the engine always have an impact one way or the other. I've seen tired engines with the guts pulled out of them ping badly even under low to moderate acceleration. Have you run a compression check?
If you have vacuum advance and have it connected to ported vacuum, try swapping to manifold va***m and reset your initial timing.
Timing and compression is what controls cylinder temps. High cylinder pressure creates high temps, the high temp creates NOx. High octane fuel means it has an increased capacity to suppress combustion in cylinders with high pressure.
Rather than trust "what a guy posted" on the internet, try looking up detonation in a decent reference source.
The Jalopy Journal
