stock 318 pinging
Quick way to ball park it for the gas your running on,keep retarding the distributor till the pinging stops at full throttle, when you can barely hear it ping back it off 2 degrees or more .I have also seen heavily carboned engines that pinged due to the excessive carbon raising the cr. Don't know if its still done but I saw mechanics years ago clean carbon deposits by pouring small amounts of water down the carb at a very fast idle.
I learned this from MR. Wilson, he was the auto shop teacher at North Hollywood High.
Easier with someone in the car the keep the revs up.
With the revs up, slowly pour a large tumbler style drinking glass full of water down the carb, being careful not to over do it and bog the engine.
MR. Wilson's demo included a piece of cardboard placed at the end of the exhaust.
After one tumbler full of water, the cardboard had a black, sticky, almost tar like deposit that had more volume than any of us expected.
Flip the cardboard and repeat, the second tumbler produced about 10% of what the first tumbler did.
It's science.
Water introduced into the combustion process turns to steam, each oxygen atom latches onto a carbon atom and heads for the exit.
This essentially steam cleans the combustion chamber, saving the back breaking work of pulling the heads scraping and wire wheeling, buying head gaskets, and putting the whole thing back together.
I would not use this process on a vehicle that has a catalytic converter.
I have a creepy feeling that sticky black tar crap that I saw on that cardboard would screw up a catalytic converter.
If you need to do this, and the system has a catalytic converter
unbolt the converter and let it hang, wire it off to the side, or hell, replace it with a Test Tube and go on with your life.
