I was never really taught by anyone about cars so I had to learn myself. Most stuff I can figure out but this I cannot. When people refer to timing (IE "My base timing is set to xº"), they mean that the spark plug fires xº before the piston is hits TDC. That is called advanced timing. Am I right so far? So here is what I dont get. Bad gas causes pre-ignition (pinging?) because its not as stable as better quality gas and when its pushed too far (too much compression) it combusts by itself, before the plug fires. Right? So if you car is pinging, why do you program/tune for less timing? For example, if you were at 12º of timing and you were pinging, you would go down to say 10º of timing. But doesnt that mean the the spark plug now fires later giving the piston more time to travel resulting in MORE compression of the air/fuel mix?? I know I am missing something here?

 

Anyone?

 

Since I was in AutoWreck class, but pinging is detonation, or the air/fuel charge igniting prematurely. This is not good for the engine since all your mechanical parts are out of postiton to accept the power. Increasing timing would make your charge fire off even earlier, stressing everything even more. If your fuel cant handle normal tuning, I'd say it was time to change brands, octane, or add a booster. If I have my facts wrong, forgive me, for time has dulled my memory and please correct me.


Mark

 

mostly right i believe, and the timing can be retarded as well as advanced, its all part of tuning...finding that happy medium between boost, compression, timing, and octane. too much(or too little) of any of these can result in a thrown rod, pierced piston, melted plugs blah blah. advancing timing too much causes detonation, retarding it helps prevent detonation (hints when people run nitrous they pull some timing) when you add timing it fires sooner and creates more power, visa versa. if it pings with even very little timing, most likely you need to richen the a/f up more