Quote Originally Posted by BajaRon View Post
Now, with fuel injection, the fuel does not enter the picture until just before the spark plug fires.
I don't think that is correct. The EFI injectors inject the fuel into the intake ports of the cylinder head, which means the fuel enters the combustion chamber along with the air. If the fuel was injected just before the spark plug fires that would mean the fuel would have to be injected directly into the combustion chamber, like a diesel engine. Look at the Fuel System section of the EFI chapter of the service manual (2014 RTS in my case).

I think one of the main reasons predetonation isn't the problem it used to be is that combustion chambers have been designed to maximize air/fuel mixing, plus there are probably no sharp corners or other small bits of metal that can get hot enough to retain heat and cause the next air/fuel charge to ignite prematurely.